... Accession Number : ADA351780. Title : Ab Initio and DFT Potential Energy Surfaces for Cyanuric Chloride Reactions. Descriptive Note : Final rept. ...

... pressure regions where dissociation, ionization, and elec ... different ab initio, DFT, or semiempirical potentials. The reference potential could rely on a ...

scaling DFT code (see Peter Haynes) Other codes used in TCM for applications ffl CPMD � DFT ab initio? (MT/RN) ffl non�collinear spins in QMC (MT) ffl Pseudopotentials for many�body calculations (Lee, Mostofi, Di'eguez) Applications etc..(CASTEP, CPMD) ffl ab initio ...

Ab initio and nonlocal density functional theory (DFT) calculations were performed to determine reaction mechanisms for formation of the six- membered ring C3N3Cl3 (cyanuric chloride) from the monomer, cyanogen chloride (ClCN). MP2 geometry optimizations ...

Ab-initio calculations within the DFT and GGA have been carried out in an attempt to understand better which property sets the activity of transition metal sulfides (TMS) in the hydro-desulfurization reaction (HDS), a most important step in the refining o...

. The previous ab initio results on lattices of K atoms for coordination numbers z 8, 4, and 2 are analyzed these DFT results for K into contact with a simple and physically appealing quantum-chemical model proposed conclusions are given at the end of the paper. II. THEORETICAL METHOD We have performed the ab ...

My efforts in the Density Functional Theory (DFT) project of Dr. Bartlett's research group have been limited to the implementation of analytical energy gradients with respect to nuclear displacement in ACES2. The most immediate benefit of this work is ana...

Presented here are results of ab initio Density Functional Theory (DFT) structural relaxations performed on dehydrogenated and monohydrogenated nanocrystalline diamond structures of octahedral (111) and cuboctahedral morphologies, up to approximately 2nm ...

Density Functional Theory (DFT) is one of the most used {\\em ab initio} theoretical frameworks in materials science. It derives the ground state properties of multi-atomic ensembles directly from the computation of their one-particle density \

A multiscale technique is developed that couples empirical molecular dynamics (MD) and ab�initio density functional theory (DFT). An overlap handshaking region between the empirical MD and ab�initio DFT regions is formulated and the interaction forces between the carbon atoms are calculated based on the ...

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Keto-enol tautomerization of 3-formylacetylacetone has been studied by NMR spectroscopy, ab initio, and DFT calculations in the gas phase and continuum solvation. By employing very low temperatures in a freonic solvent, tautomeric and conformational equilibria in the slow exchange regime were analyzed in detail. The beta-tricarbonyl ...

It is essential to know the arrangement of the atoms in a material in order to compute and understand its properties. Searching for stable structures of materials using first-principles electronic structure methods, such as density-functional-theory (DFT), is a rapidly growing field. Here we describe our simple, elegant and powerful approach to searching for structures with ...

It is essential to know the arrangement of the atoms in a material in order to compute and understand its properties. Searching for stable structures of materials using first-principles electronic structure methods, such as density-functional-theory (DFT), is a rapidly growing field. Here we describe our simple, elegant and powerful approach to searching for structures with ...

Conventional density functional theory (DFT) fails for materials with strongly correlated electrons, such as late transition metal oxides. Large errors in the intra-atomic Coulomb and exchange interactions are the source of this failure. The DFT+U method has provided a means, through empirical parameters, to correct these errors. Here, we present a ...

We present a generalized definition of subspace occupancy matrices in ab initio methods for strongly correlated materials, such as DFT+U (density functional theory + Hubbard U) and DFT+DMFT (dynamical mean-field theory), which is appropriate to the case of nonorthogonal projector functions. By enforcing the ...

We report herein a series of ab initio simulations of water under both static and shocked conditions. We have calculated the coherent x-ray scattering intensity of several phases of water under high pressure, using ab initio Density Functional Theory (DFT). We provide new atomic scattering form ...

Recently, we introduced a new density-functional theory (DFT) approach for the calculation of NMR shielding constants. First, a hybrid DFT calculation (using 5% exact exchange) is performed on the molecule to determine Kohn-Sham orbitals and their energies; second, the constants are determined as in nonhybrid DFT theory, that is, the ...

Properties of molecules solvated in ionic liquids (ILs) are strongly affected by solvent environment. For this reason, to give reliable results, ab initio calculations on solutes in ILs, including ions constituting ionic liquid itself, have to self-consistently account for the change of both electronic and classical solvation structure in ILs. Here, we ...

Scanning tunneling microscopy (STM) and ab initio calculations based on density functional theory (DFT) were used to study the self-aligned silicon nanoribbons on Ag(110) with honeycomb, graphene-like structure. The silicon honeycombs structure on top of the silver substrate is clearly observed by STM, while the ...

The rotational dynamics of methyl groups in 2,6 dimethylpyrazine and in cobalt and nickel acetates have been studied by neutron scattering and a combination of ab initio and empirical calculations. These results and the precision of the method are compared to those obtained by DFT calculations in each case. It has been shown that ...

The rotational dynamics of methyl groups in 2,6 dimethylpyrazine and in cobalt and nickel acetates have been studied by neutron scattering and a combination of ab initio and empirical calculations. These results and the precision of the method are compared to those obtained by DFT calculations in each case. It has been shown that ...

is commonly used to quantify the strength of a Lewis acid.14�16 DFT calculations on the zeolite, mordenite,14 strong Lewis acidity; for instance, the DFT calculated BE for NH3 at strong Lewis acid sites on mordenite

Density functional theory (DFT) was examined for computing energies of temporary anions having negative electron affinities ranging from -8.0 to -0.2 eV. The calculated electron affinities are in good agreement with experiment for {pi}* states and low-energy {sigma}* states. The dependence of the DFT results on basis set was investigated. Comparisons are ...

The framework of ab initio density-functional theory (DFT) has been introduced as a way to provide a seamless connection between the Kohn-Sham (KS) formulation of DFT and wave-function based ab initio approaches [R. J. Bartlett, I. Grabowski, S. Hirata, and S. Ivanov, J. ...

Time-dependent density functional theory (TD-DFT) and correlated ab initio methods have been applied to the electronically excited states of vitamin B12 (cyanocobalamin or CNCbl). Different experimental techniques have been used to probe the excited states of CNCbl, revealing many issues that remain poorly understood from an electronic ...

Quantum chemical calculations of energies, geometrical structure and vibrational wave numbers of 3,4-dimethoxybenzonitrile (DMBN) were carried out by the ab initio Hartree-Fock (HF) and density functional theory (DFT) with complete relaxation in the potential energy surface using 6-311++G(d,p) basis set. The computed values of ...

The ab-initio calculations based on density functional theory (DFT) are performed for Fe and C in their ground state crystal structures. Heats of formation are then calculated for different Fe-C alloy compounds. The lattice constant (volume), bulk modulus and shear moduli for cementite are determined from the total energy calculations. These material ...

The INS spectra of several azines have been analyzed starting from force constant matrix calculated via ab initio and DFT methods. In order to reproduce both vibrational frequencies and intensities, the initial force constants must be fitted until the spectral profile is reproduced. We have checked the various ways which can be ...

Ab initio and density functional theory (DFT) methods at the HF/6-31G*, B3LYP/6-31G*, MP2/6-31G*, and MP2/TZVP levels of theory were applied to the investigation of the relative stability of six fullerene isomers of C32. Full geometry optimization of the systems was carried out and electrostatic potential distributions were calculated. ...

An ab initio density functional theory-based study of the electronic band structure, the elastic, electric, elastoelectric, and linear and nonlinear optical properties of the new ion conductor LiB6O9F, has been performed. The computed band structure reveals a wide direct band gap. The coefficients of the second order nonlinear susceptibility ?(2) were ...

The FT-IR and FT-Raman spectra of 3-Bromo phenol (3-BP) molecule have been recorded using Bruker IFS 66V spectrometer in the range of 4000-100 cm(-1). The molecular geometry and vibrational frequencies in the ground state are calculated by using the ab initio Hartree-fock (HF) and DFT (B3LYP) methods with 6-31G (d, p) and 6-311G (d, p) ...

The molecular vibrations of xanthine were investigated in polycrystalline sample, at room temperature by Fourier transform infrared (FTIR) and FT-Raman spectroscopies. The spectra of the molecule have been recorded in the regions 4000-50 cm(-1) and 3500-100 cm(-1), respectively. Theoretical information on the optimized geometry, harmonic vibrational frequencies, infrared and Raman intensities were ...

The Fourier transform infrared (FTIR) and FT-Raman spectra of p-cyanobenzoic acid (CBA) have been recorded in the range 4000-400 and 4000-100 cm(-1), respectively. The complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the observed FTIR and FT-Raman data. The vibrational frequencies determined experimentally were compared with theoretical ...

A general set of methods is presented for calculating chemical potentials in solid and liquid mixtures using {\\em ab initio} techniques based on density functional theory (DFT). The methods are designed to give an {\\em ab initio} approach to treating chemical equilibrium between coexisting ...

We present a comprehensive set of results for water, a case study of a hydrogen-bonded system, using the self-consistent polarization density functional theory (SCP-DFT). With minimal parametrization, SCP-DFT is found to give good results for the interaction energy of the dimer; the geometries, cohesion energies, and harmonic frequencies of larger ...

Collision processes between a single gold atom and a gold cluster are investigated by means of ab initio techniques. The targets we consider are minimum energy 13 gold atom clusters. The kinetic energy of the projectile and its impact parameter are chosen within a range such that the three regimes we are mainly interested in studying (fusion, scattering ...

The peptide bond energy variation of methionine-alanine dipeptide was calculated using HF, DFT and MP2 ab-initio methods with 6-31G and 6-31++G** basis sets. The energy variation for MP2 method shows that as the distance between the two amino acid moieties is increased, the interaction energy between them decreases to negative infinity. The Hartree-Fock ...

Sm{sub 2}O{sub 3} was compressed at room temperature up to 44.0 GPa and then decompressed back to ambient pressure. In situ X-ray diffraction was used to monitor the structural changes in the sample. A cubic to hexagonal phase transformation was observed in Sm{sub 2}O{sub 3} for the first time. After decompression back to ambient pressure, the hexagonal phase was not quenchable and transformed to ...

The optimized geometry and vibrational frequencies of P-N,N-dimethylaminobenzylidenemalononitrile (DBM) were obtained by ab initio HF and DFT/B3LYP levels with complete relaxation in the potential energy surface using 6-31++G(d,p) and 6-311++G(d,p) basis sets. The Fourier-transform infrared (FT-IR) spectrum of DBM has been recorded in ...

... This study involves: Ab-initio crystal orbitals and polymer orbitals; Ab-initio coupled cluster program; Ab-initio quantum chemical calculations and ...

During the past decade, computer simulations based on a quantum-mechanical description of the interactions between electrons and between electrons and atomic nuclei have developed an increasingly important impact on solid-state physics and chemistry and on materials science-promoting not only a deeper understanding, but also the possibility to contribute significantly to materials design for ...

The structure, potential energy functions and vibrational spectra of several cyclic and bicyclic molecules have been investigated using several spectroscopic techniques and high-level ab initio and density functional theory (DFT) calculations. Laser induced fluorescence and Raman spectroscopies were used to study the conformation of 2- ...

This work describes the extension of a previously reported empirical localized orbital correction model for density functional theory (DFT-LOC) for atomization energies, ionization potentials, electron affinities, and reaction enthalpies to the correction of barrier heights for chemical reactions of various types including cycloadditions, cycloreversions, dipolar ...

In order to test the vibration-transit (V-T) theory of liquid dynamics, ab initio density functional theory (DFT) calculations of thermodynamic properties of Na and Cu are performed and compared with experimental data. The calculations are done for the crystal at T=0 and Tm , and for the liquid at Tm . The key theoretical ...

FT-IR (4000-400 cm(-1)) and FT-Raman (3500-50 cm(-1)) spectral measurements of solid sample of 2-chloro-5-bromopyridine have been done. Ab initio and DFT calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, depolarization ratios, IR intensities, Raman activities and atomic ...

We describe large scale ab initio quantum chemical and mixed quantum mechanics/molecular mechanics (QM/MM) methods for studying enzymatic reactions. First, technical aspects of the methodology are reviewed, including the hybrid density functional theory (DFT) methods that are typically employed for the QM aspect of the calculations, ...

... Title : Chalcopyrite Magnetic Semiconductors: An Ab-Initio Study of Their Structural, Electronic and Magnetic Properties. ...

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... COMPENDIUM OF AB INITIO CALCULATIONS ...

... Accession Number : ADA219907. Title : An Ab Initio Study of the Geometry and Rotational Barrier of 4- Phenylimidazole. ...

... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : Ab Initio Calculations of the ...

... Title : Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields. ...

... Title : AB Initio Quantum Chemical Investigations of Solubilities in Supercritical Solutions. Descriptive Note : Conference Paper,. ...

Misfolded metallo-proteins are potential causal agents in the onset of neuro-degenerative diseases, such as Alzheimer's and Parkinson's Diseases (PD). Experimental results involving metal chelation have shown significant promise in symptom reduction and misfolding reversal. We explore, through atomistic simulations, potential reaction pathways for the chelation of Cu^2+ from the metal binding site ...

The infrared spectra (3500-50 cm(-1)) of the gas and solid and the Raman spectra (3500-50 cm(-1)) of the liquid and solid have been recorded for 1-fluoro-2-butyne, CH3-C-triple bond-C-CH2F. Equilibrium geometries and energies have been determined by ab initio and hybrid DFT methods using a number of basis sets. A vibrational assignment ...

The Fourier transform infrared (FTIR) and FT-Raman spectra of 4-amino-2-methylquinoline (AMQ) have been recorded in the range 4000-400 and 4000-100 cm(-1), respectively. The experimental vibrational frequency was compared with the wavenumbers obtained theoretically by ab initio HF and DFT-B3LYP gradient calculations employing the ...

images/logoetsf Introduction Electron Energy Loss Spectroscopy Applications: Nanotubes and Graphene Perspectives Ab Initio calculations of electronic excitations Carbon Nanotubes and Graphene layer systems and Graphene Perspectives Outline 1 Introduction 2 Electron Energy Loss Spectroscopy Linear response within DFT

Theoretical Insight into the Interactions of TMA-Benzene and TMA-Pyrrole with B3LYP Density theoretical investigation of the tetramethylammonium(TMA)-benzene and TMA-pyrrole complexes has been performed density in the 5 6 aromatic system of pyrrole is larger than that in the 6 6 system of benzene

We report on the quantitative electronic spectroscopy of cyanodiacetylene in far-UV (accessed by the absorption of synchrotron radiation) and in mid-UV ranges. The assignment of vibronic bands in mid-UV is assisted by quantum-chemical calculations of vibrational frequencies in the excited electronic state, at ab-initio (CIS) and time-dependent DFT levels ...

the semiempirical AM1 (37) method and ab initio DFT with the functional of Perdew, Burke, and Ernzerhof (38., Cohen, M. L., Louie, S. G. & Zettl, A. (1995) Science 269, 966�967. 33. Feldman, Y., Wasserman, E. J. P. (1985) J. Am. Chem. Soc. 107, 3902�3909. 38. Perdew, J. P., Burke, K. & Ernzerhof, M. (1996

to the photolysis and reactions of CCl4. Studies using radiolysis of CCl4 in methyl cyclohexane at low temperatures EXAFS study on CBr4 in cyclohexane did not show any photodissociated intermediates.24 Due Most of the calculations were performed in a nonpolar solvent, cyclohexane with a dielectric constant

GRAPHICS&MODELING DESCRIPTORS v) -besides computed molecular descriptors by some quantum chemical or QSAR&QSAR Methodology: other methods Methodology: selected molecular descriptors Results: chemometrics for set I Results and modeling of progestogen-receptor was performed. Besides DFT ab initio computed molecular descriptors ...

The topological diversity of lithium-boron imidazolates LiB(imid)(4) was studied by combining topological enumeration and ab initio DFT calculations. The structures based on zeolitic rho, gme and fau nets are shown to be stable and have high total hydrogen uptake (6.9-7.8 wt.%) comparable with that of MOF-177. PMID:21125132

We employ atomic first principles theory to study the properties of realistic graphene nanoelectronic systems. We focus on the role of different contact materials and their effect on the transport properties at the graphene/metal junction. The current-voltage characteristics were calculated using density functional theory (DFT) combined with non-equilibrium Green's functions ...

Ab initio calculations have been carried out on 3-methyl indole, and the cation and neutral radicals of 3-methyl indole, using Density Functional Theory (DFT), the Becke3-Lee-Yang-Parr functional, and the 6-31G*, 6-31+G*, 3-21G*, and TZ2P basis sets. Opti...

The C-H bond dissociation energy of acetylene was computed by both ab initio approaches and density functional theory in a local density approximation (DFT-LDA). Structures and energies for acetylene and its dissociation products (the ethynyl and hydrogen...

The Faddeev random phase approximation (FRPA) method is applied to calculate the ground state and ionization energies of simple atoms. First ionization energies agree with the experiment at the level of {approx}10 mH or less. Calculations with similar accuracy are expected to provide information required for developing the proposed quasiparticle-DFT method.

Geometry optimizations and normal-mode analyses of three conformers of 1,3,5-trinitro-s-triazine (RDX) are performed using second-order Moller-Plesset (MP2) and nonlocal density functional theory (DFT) methods. The density function used in this study is B...

We have simulated with in the Density Functional Theory (DFT) spherically cut nano-diamonds from bulk diamond at ambient conditions. The 2.6 nanometer diameter sphere is then allowed to relax at 250K and surface reconstruction is observed. Four hemispherical fullerene like regions form on the surface and while the interior maintains the diamond structure, it undergoes ...

With blooming experimental synthesis of various nanostructures out of many semiconductor materials, there is an urgent need to calculate the electronic structures and optical properties of these nanosystems based on reliable ab initio methods. Unfortunately, due to the O(N^3) scaling of the conventional ab initio ...

We analyze the ability of spin-flip time dependent density functional theory (TD-DFT) to uniformly describe excited states of single, double, and mixed excitation character in closed-shell molecular systems, using the polyene oligomers as a primary test case. The results of comparison between conventional and spin-flip TD-DFT and with correlated ...

Energy and free energy barriers for acetaldehyde conversion in aldehyde oxidoreductase are determined for three reaction pathways using quantum mechanical/molecular mechanical (QM/MM) calculations on the solvated enzyme. Ab initio single-point QM/MM energies are obtained at the stationary points optimized at the DFT(B3LYP)/MM level. ...

... Title : AB Initio Study of the Electronic Magnetic Circular Dichroism ... functions are determined using as initio quantum chemical techniques including ...

The structure and properties of self-trapped excitons (STE), were investigated using density functional theory (DFT) and wavefunction based methods (UHF, UMP2, CAS-SCF and ccsd(t)). The accuracy of DFT results was investigated by performing more accurate electronic structure calculations on cluster configurations extracted from bulk ...

We perform a comparative ab initio study of Mn-doped germanium semiconductor using the Perdew-Burke-Ernzerhof exchange-correlation functional, density functional theory (DFT)+U, and Heyd-Scuseria-Ernzerhof hybrid functional (HSE). We show that the HSE functional is able to correctly account for the relevant ground-state properties of ...

Structure, stability and reactivity of several metal clusters with or without hydrogen doping were studied using standard ab initio and density functional theory (DFT) calculations. Conceptual DFT-based reactivity descriptors and the associated electronic structure principles lend additional support towards ...

We present a potential energy surface (PES) for the cyclotrimethylene trinitramine (RDX) dimer obtained using symmetry-adapted perturbation theory based on the Kohn-Sham density functional theory (DFT) description of the monomers [SAPT(DFT)]. More than a thousand dimer configurations were computed using an augmented double-zeta-quality basis set ...

A systematic vibrational spectroscopic assignment and analysis of benzohydrazide (BH) has been carried out by using FTIR and FT-Raman spectral data. The vibrational analysis were aided by electronic structure calculations--ab initio (RHF) and hybrid density functional methods (B3LYP and B3PW91) performed with 6-31G(d,p) and 6-311++G(d,p) basis sets. ...

This commentary focuses on the conceptual interpretation of the bonding of O(2) and NO to heme in oxyheme and nitrosylheme complexes, using high-level ab initio complete active space self-consistent field (CASSCF)/molecular mechanical (MM), gas-phase CASSCF, and CASSCF followed by second-order perturbation theory (CASPT2) calculations as well as density ...

Density-functional theory (DFT) based ab initio/ molecular dynamics (AIMD) is a promising method for calculating high-temperature thermodynamic properties of solids and liquids. Nevertheless, computational expense associated with AIMD simulations has prevented general adoption of these methods. We show that substantial savings of ...

At present there are two vastly different ab initio approaches to the description of the many-body dynamics: the density functional theory (DFT) and the functional integral (path integral) approaches. On one hand, if implemented exactly, the DFT approach can allow in principle the exact evaluation of arbitrary ...

Quantum chemical calculations of HgXn (X=F, Cl, Br, and I; n=1, 2, and 4) in the gas phase are performed using the density functional theory (DFT), two-component spin-orbit (SO) DFT, and high-level ab initio method with relativistic effective core potentials (RECPs). Molecular geometries, vibrational frequencies, ...

Quantum chemical calculations of HgX(n) (X=F, Cl, Br, and I; n=1, 2, and 4) in the gas phase are performed using the density functional theory (DFT), two-component spin-orbit (SO) DFT, and high-level ab initio method with relativistic effective core potentials (RECPs). Molecular geometries, vibrational frequencies, ...

The infrared (150 3500 cm?1) spectra have been recorded for tris(4-N?-dichloro(thio)phosphonyl)-(N?-methyl-diazobenzene)monothiophosphate. This compound includes structural parts of elementoorganic dendrimers: a core, repeated units and terminal P Cl groups. The structural optimization and normal mode analysis are performed for elementoorganic dendrimer on the basis of the ab ...

Isotropic 13C chemical shifts of the ribose sugar in model RNA nucleosides are calculated using SCF and DFT-GIAO ab initio methods for different combinations of ribose sugar pucker, exocyclic torsion angle, and glycosidic torsion angle. Idealized conformations were obtained using structures that were fully optimized by ...

Reaction enthalpies and barrier heights of the reactions CF3Br+H-->CF3+HBr {reaction (1)} and CF3CHFCF3+H-->CF3CFCF3+H2 {reaction (2)} have been calculated at the near state-of-the-art ab initio level, and also by employing the B3LYP, BH&HLYP, BB1K, MPW1K, MPWB1K and TPSS1KCIS functionals. In addition, the integrated molecular orbital+molecular ...

Due to recent advances in methods and computers, the accuracy of ab calculations has reached a point

Ultra high temperature ceramics including ZrB2 and HfB2 are characterized by high melting point, good strength, and reasonable oxidation resistance. These materials are of interest for use as sharp leading edges for hypersonic vehicles among other applications. Progress in computational modeling of UHTCs has been limited in part due to the absence of suitable interatomic potentials. We present a ...

We have tested approaches for molecular-dynamics simulations of the ion properties in high-energy-density matter. The scheme incorporates quantum corrections within the potentials used in the classical molecular-dynamics simulation. Thus, a significantly larger number of particles in the simulation box as in ab initio simulations can be used. Two types of ...

We investigate a reaction of boron trichloride (BCl3) with iron(III) hydroxide (Fe(OH)3) by ab initio quantum chemical calculation as a simple model for a reaction of iron impurities in BCl3 gas. We also examine a reaction with water. We find that compounds such as Fe(Cl)(OBCl2)2(OHBCl2) and Fe(Cl)2(OBCl2)(OHBCl2) are formed while producing HCl and ...

We have calculated crystal structures and electronic properties of Xe-H2 compounds under high pressures using first-principles density functional theory calculations and ab-initio random structure searching. We present results for the equation of state, Xe-Xe separations, and the electronic charge transfer between the Xe and H atoms. Our results are broadly consistent with ...

On the basis of ab initio calculations employing density functional theory (DFT) we investigate half metallic ferromagnetism in zinc-blende and wurtzite compounds composed of group I/II metals as cations and group V elements as anions. We find that the formation of ferromagentic order requires large cell volumes, high ionicity and a ...

Detailed ab initio studies on the electronic structure and optical properties of crystalline strontium azide and barium azide have been performed using density functional theory (DFT) within the generalized gradient approximation (GGA). Relaxed crystal structures compare well with experimental data. An analysis of electronic structure, ...

Gas-phase activation energies were calculated for three lithium enolate reactions by using several different ab initio and density functional theory (DFT) methods to determine which levels of theory generate acceptable results. The reactions included an aldol-type addition of an enolate to an aldehyde, a proton transfer from an alcohol ...

The static and dynamic properties of liquid Sn at two di?erent thermodynamic states have been studied from the Orbital Free Ab-Initio Molecular Dynamics (OFAIMD) simulation method. This method is based on the density functional theory (DFT) of Hohenberg and Kohn. The exchange and correlation interaction is described here with the local density ...

This talk presents the result of an ab-initio study of Ruddlesden-Popper(RP) phases for Srn+1TinO3n+1(n = 1, 2, 3, ?) compounds with the density functional theory(DFT). In particular, we present results for the relation between octahedral rotations and external strains. We find that rotational reconstructions are energetically favorable under nonzero ...

Ab initio density functional theory (DFT) and density function perturbation theory (DFPT) have been used to investigate the thermal properties of the fcc Al3Mg and Al3Sc alloys over a wide range of pressure and temperature, in comparison with fcc Al. Phonon dispersions were obtained at equilibrium and strained configurations by density ...

129Xe nuclear shielding tensor is calculated at the leading-order, one-electron Breit-Pauli perturbation theory (BPPT) level for the xenon fluorides XeF+, XeF2, XeF3+, and XeF4 that cover the large nuclear magnetic resonance chemical shift range of this nucleus. BPPT is found to improve the shift range and relative shifts as compared to the nonrelativistic (NR) theory. While the full BPPT ...

In this work, we examine the performance of a range of local and hybrid DFT functionals (including BLYP, PBE, PW91, B3P86, B3LYP, and TPSS), new generation DFT functionals (including KMLYP, BMK, M05, and M05-2X), and DFT functionals with the explicit empirical correction for dispersion interactions (including BLYP-D, PBE-D, and ...

We calculate the static structure factor of dense multi-component plasmas. Large scale ab initio finite-temperature DFT molecular dynamics simulations are performed in order to cover the region where a consistent quantum treatment for the electrons is inevitable. Especially, the behavior at small wave numbers k can be inferred from the ...

The standard molar enthalpies of formation in the gaseous state of a series of nitrophenols, 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 5-methyl-2-nitrophenol, 2-methyl-5-nitrophenol, and 3-methyl-4-nitrophenol, have been obtained from combustion calorimetry and results from the temperature dependence of the vapor pressure measured by the transpiration method. To verify the experimental data, ...

The multiconfigurational CASSCF/CASPT2 approach, along with various functionals of density functional theory, is applied to selected iron(II)-nitrosyl ({FeNO}(7)) complexes, both with heme and nonheme groups. The energetics of the lowest doublet and quartet spin states at the correlated ab initio (CASPT2) level is presented for the first time. Comparison ...

The electronic structure of the ScN and ScP molecules is a subject of controversy and turns out to be a challenging problem in quantum chemistry. We show that the ground-state electronic structure for both molecules depends critically on the choice of methods used which incorporate different ways of accounting for electron correlation. A parallel ab ...

Since the interior structure of giant planets inside or outside our solar system cannot be probed directly by experiments, planetary models have been developed to gain further insight. Such models require accurate equations of state (EOS) for the major components (H, He, and heavier compounds like water) up to extreme thermodynamic conditions (pressures of several ten megabars and temperatures of ...

The energy, geometrical parameters and vibrational wavenumbers of crotonaldehyde were calculated by using ab initio and B3LYP with 6-31G(d,p) and 6-311G(d,p) basis sets. The FT-IR and FT-Raman spectra for liquid state crotonaldehyde have been recorded in the region 3400-400cm(-1) and 3400-100cm(-1), respectively and compared with the theoretical ...

We present an interpretation of the intermolecular transfer integral that is independent from the origin of the energy scale allowing convergence studies of this important parameter of organic molecular materials. We present extensive numerical studies by using an ethylene pi dimer to investigate the dependence of transfer integrals on the level of theory and intermolecular packing. Transfer ...

Zircon and Reidite are the polymorphs of ZrSiO4 minerals that are natural hosts of various radioactive elements in the crust of the earth. Its high permittivity also makes it a promising material for the gate dielectric material in metal-oxide semiconductors. Knowledge of the thermodynamic properties at high temperature and high is very important to consider its application as an effective natural ...

Unbiased open-ended methods for finding transition states are powerful tools to understand diffusion and relaxation mechanisms associated with defect diffusion, growth processes, and catalysis. They have been little used, however, in conjunction with ab initio packages as these algorithms demanded large computational effort to generate even a single event. ...

The optical absorbance and surface photovoltage of slabs of Si with varying number of layers have been calculated starting from their atomic structure. Results have been obtained for nanostructured surfaces with adsorbed metal clusters and for group III and V dopants, from ab initio DFT with periodic boundary conditions for extended ...

Yohimbine hydrochloride (YHCl) is an aphrodisiac and promoted for erectile dysfunction, weight loss and depression. The optimized geometry, total energy, potential energy surface and vibrational wavenumbers of yohimbine hydrochloride have been determined using ab initio, Hartree-Fock (HF) and density functional theory (DFT/B3LYP) ...

We present an implicit solvent model for ab initio electronic-structure calculations which is fully self-consistent and is based on direct solution of the nonhomogeneous Poisson equation. The solute cavity is naturally defined in terms of an isosurface of the electronic density according to the formula of Fattebert and Gygi (J. Comput. Chem., 23 (2002) ...

A test set of four molecules was formed by considering the bonding in the open (C2v) and ring (D3h) forms of ozone, and the open and ring isomers of sulfur dioxide (both of C2v symmetry). This test set was used as to assess the performance of various Density Functional Theory (DFT) methods in (hyper)polarizability calculations against well established ab ...

A density functional theory (DFT), time-dependent DFT, and ab initio second order M�ller-Plesset perturbation theory study of the aggregation of the metal free indoline D102 and D149 dyes on extended TiO(2) models is reported. By selecting the relevant dimeric arrangements on the TiO(2) surface and evaluating, at ...

Accurate interaction energies of nonpolar (argon) and polar (water) adsorbates with graphene-based carbon allotropes were calculated by means of a combined density functional theory (DFT)-ab initio computational scheme. The calculated interaction energy of argon with graphite (-9.7 kJ mol(-1)) is in excellent agreement with the available experimental data. ...

The modern versions of the density functional theory (DFT), especially those using the generalized gradient approximation (GGA), have reached (almost) chemical accuracy and thus can be applied to study problems of real chemical interest such as catalysis. The important equations for the DFT, the local density approximation (LDA), and GGA are given. The ...

In order to model electronic transport properties of atomic and molecular scale nanoelectronic devices and nanostructures under external bias and gate potentials, we have developed a self-consistent ab initio method by performing density functional theory (DFT) analysis within the Keldysh nonequilibrium Green's functions (NEGF) ...

This paper reports on the growth and characterization of the structural and mechanical properties of tantalum zirconium nitride films and the subsequent simulation of these properties using an ab initio calculation based on density functional theory (DFT) within the generalized gradient approximation. The films were deposited by ...

Unbiased open-ended methods for finding transition states are powerful tools to understand diffusion and relaxation mechanisms associated with defect diffusion, growth processes, and catalysis. They have been little used, however, in conjunction with ab initio packages as these algorithms demanded large computational effort to generate even a single event. ...

We present a systematic study of isolated hydrogen in ?-TeO2 (paratellurite) by means of muon-spin spectroscopy measurements complemented by ab initio calculations based on density-functional theory (DFT). The observable metastable states accessible by means of the muon implantation allowed us to probe both the donor and the acceptor ...

A hybrid computational method intended for simulations of biomolecules in solution is described. The ab initio Kohn-Sham (KS) density functional theory (DFT) method is used to describe the chemically active part of the system and its first solvation shells, while a frozen-density orbital-free (FDOF) DFT method is ...

The FT-IR and FT-Raman vibrational spectra of 1,3-dichlorobenzene (1,3-DCB) have been recorded using Bruker IFS 66V Spectrometer in the range 4000-100cm(-1). A detailed vibrational spectral analysis has been carried out and assignments of the observed fundamental bands have been proposed on the basis of peak positions and relative intensities. The optimized molecular geometry, vibrational ...

Ab initio calculations are becoming increasingly useful to engineers interested in designing new alloys because these calculations are able to accurately predict basic material properties only knowing the atomic composition of the material. Fundamental physical properties (like formation energy and elastic constants) of 11 bcc magnesium-lithium alloys were ...

Fully filled CaCo4Sb12 system is selected as a test case for probing how the ab-initio modeled electronic transport properties are affected by the computational level. The periodic wave functions for the various adopted models are calculated by means of the Density Functional Theory (DFT) approach using local gaussian atomic basis sets, while the relevant ...

The FT-IR and FT-Raman vibrational spectra of alpha-chlorotoluene have been recorded using Perkin-Elmer 180 spectrometer in the range 3600-10 cm(-1) in the solid phase. A detailed vibrational spectral analysis has been carried out and assignments of the observed fundamental bands have been proposed on the basis of peak positions and relative intensities. The optimized molecular geometry, ...

... AB-INITIO SIMULATION OF a/2110> ... 4. TITLE AND SUBTITLE AB-INITIO SIMULATION OF a/2110> SCREW DISLOCATIONS γ-TiAl 5c. ...

... ADP012740 TITLE: Ab Initio Study on Spin Polarization of III-V Compound Tips ... Ab initio study on spin polarization of III-V compound tips ...

Ab initio electronic structure methods can supplement CALPHAD in two major ways for subsequent applications to stability in complex alloys. The first one is rather immediate and concerns the direct input of ab initio energetics in CALPHAD databases. The o...

...with this part. The certificate shall be void ab initio for those vehicles causing the...issued, and the certificate may be deemed void ab initio. (C) The manufacturer...with this part. The certificate shall be void ab initio for those vehicles causing...

The infrared and Raman spectra of liquid and vapor-phase 2-fluoropyridine and 3-fluoropyridine have been recorded and assigned. Ab initio and DFT calculations were carried out to compute the molecular structures and to verify the vibrational assignments. The observed and calculated spectra agree extremely well. The ring bond distances ...

Ab initio calculation performed by density functional theory (DFT) and the broken bond model are utilized to systemically determine the surface energies of ceramics with B1 or NaCl structure ?100 where the subscript shows the index of surfaces. The ceramics includes the transition metal carbides (TMC) and the transition metal nitrides ...

carried out by using VASP soft- ware package: G. Kresse and J. Hafner, Phys. Rev. B 47, R558 1993 ; G The methodology of the TRANSIESTA-C software package is de- scribed in: M. Brandbyge, J.-L. Mozos, P. Ordej�n, J-C, a recently developed ab initio transport software based on DFT, localized basis sets, and nonequilib- rium

Structural properties of energetically low-lying isomers of the isolated Al O molecular system have been investigated by theoretical ab initio techniques within the Hartree-Fock HF and second-order Moller-Plesset MP2 frozen core level of approximation and density functional methods DFT employing the Becke-3-Perdew-86 B3P86 hybrid ...

We present spin-unpolarized DFT study for band structures, density of states and transmission of armchair graphene nanoribbons (AGNRs) using local density approximations (LDA). The band gaps of AGNRs were found to vary randomly with the width of ribbon and they show semiconducting behavior. We have used oxygen as a dopant in AGNRs and observed the metallicity and ...

The distonic dimer radical cation of the 2,3-dihydrofuran was radiolytically generated in Freon matrix and studied by low-temperature EPR spectroscopy. The structure of the dimer radical cation was also investigated using different quantum chemical methods. The BH&HLYP, similarly as ab initio HF and MP2 methods, predict in agreement with the experiment ...

A chloride complex of a hexaprotonated azamacrocycle has been isolated, and its structure has been determined by X-ray crystallography showing two encapsulated chloride anions in the cavity. The two internal guests are coordinated at two binding sites on the opposite side of the macrocycle through trigonal recognition by hydrogen-bonding interactions. The other four chlorides are located outside ...

2-Chloroethylisocyanate has been studied in a thorough way. NMR, Raman, FTIR, and Ar-matrix vibrational spectra of the molecule are presented and discussed with the complement of ab initio and DFT methods. The spectroscopic results reveal the existence of anti and gauche conformers that are equally populated in the gas phase. Thermal ...

The Raman spectrum of terbutaline hemisulphate is reported for the first time, and molecular assignments are proposed on the basis of ab initio BLYP DFT calculations with a 6-31G* basis set and vibrational frequencies predicted within the quasi-harmonic approximation; these predictions compare favourably with the observed vibrational ...

The effective molarity (EM) for 12 intramolecular S(N)2 processes involving the formation of substituted aziridines and substituted epoxides were computed using ab initio and DFT calculation methods. Strong correlation was found between the calculated effective molarity and the experimentally determined values. This result could open a ...

The conformational states of diglyme in both the solid and liquid states have been determined by an integrated use of both IR and Raman spectroscopy together with ab initio/density functional theory (DFT) calculations. Using knowledge from diglyme also made possible the study of the conformational state of longer glymes, including a ...

We use a tight-binding model that is fit to ab-initio DFT-GGA electronic-structure calculations for zirconium. >From this model we calculate elastic constants and zero-temperature phonons within the quasi-harmonic approximation. The knowledge of phonon spectra for different crystal structures and at different pressures allows us to evaluate the Gibbs ...

[reaction: see text] Ab initio and density functional theory (DFT) calculations were used to examine the mechanisms of reduction and amination of chloromethane by lithium dimethylaminoborohydride (LAB) in the gas phase. For comparison, the amination of chloromethane by lithium dimethylamide and the reduction by borane, diborane, and ...

Structural analysis of an adduct of a thiophene-based cryptand with tosylic acid shows the formation of a hybrid amine-water cyclic pentamer composed of four water molecules and one protonated amine in the charged hydrophobic cavity. The bulky tosylate groups remain outside the cavity, making the ligand favorable for hosting water molecules. Ab initio ...

From Ab Initio calculations, we compare the energy of amorphous Iron to bcc and fcc Iron structures, both at zero pressure and high pressure. From these calculations we draw conclusions on the properties of metallic glass structures over a range of pressure. Additionally, we address the adsorption energy of Oxygen on amorphous surfaces versus the ...

Dispersion-interaction corrected DFT simulations are performed to study the structure of two allomorphs of native cellulose I. Good agreement between theoretical and experimental data is achieved. Two H-bond patterns, previously identified experimentally, are examined for both allomorphs. The transition mechanism for the conversion between the phase I(?) and I(?) is studied by ...

Methanol to gasoline is one of the most studied and important application of zeolites in current commercial production. We have performed an extensive simulation of the most important steps of the process, namely formation of the first intermediate, dimethyl ether, and of formation of the first C-C bonds. The simulations were based on a combination of ab ...

Epoxidation made easy: Subnanometer gold clusters immobilized on amorphous alumina result in a highly active and selective catalyst for propene epoxidation. The highest selectivity is found for gas mixtures involving oxygen and water, thus avoiding the use of hydrogen. Ab initio DFT calculations are used to identify key reaction ...

Subnanometer gold clusters immobilized on amorphous alumina result in a highly active and selective catalyst for propene epoxidation. The highest selectivity is found for gas mixtures involving oxygen and water, thus avoiding the use of hydrogen. Ab initio DFT calculations are used to identify key reaction intermediates and reaction ...

A theoretical study of rotational profiles of molecular absorption bands is essential for direct comparison with observations of diffuse interstellar bands. Applications using gaussian quantum-chemical approach within DFT are presented. Structural and vibrational properties of the polycyclic aromatic hydrocarbon ovalene cation (C32H14+) are obtained. We discuss the expected ...

A Combination of quantum and classical calculations has been performed to investigate the hydrogen storage in single-walled carbon nanotubes (SWNTs). The ab-initio calculations at the Density Functional level of Theory (DFT) show the nature of hydrogen interaction in selected sites of a (5,5) tube walls. On top of this, Molecular Dynamics simulations model ...

Applied Physics A r. pentcheva Ab initio study of microscopic processes in the growth of Co on Cu(001-89-2180-4334, E-mail: pentcheva@lrz.uni-muenchen.de Present address: Section Crystallography, Dept. of Earth.59 � 0.1 eV is derived from the ex- perimental data, which is in good agreement with the DFT- #12;PENTCHEVA

The dynamic compression of molten metals including Sn is of current interest. In particular, experiments on the compression of molten Sn by Davis and Hayes will be described at this conference. Supporting calculations of the equation of state and structure of molten Sn as a function of temperature and pressure are in progress. The calculations presented are ab ...

We use two fundamental theoretical frameworks to study the finite-size (shell) properties of the unitary gas in a periodic box: (1)�an ab�initio quantum Monte�Carlo (QMC) calculation for boxes containing 4 to 130 particles provides a precise and complete characterization of the finite-size behavior, and (2)�a new density functional theory (DFT) ...

The Kohn-Sham (KS) potential of density-functional theory (DFT) emerges as the minimizing effective potential in a variational scheme that does not involve fixing the unknown single-electron density. Using Rayleigh Schr�dinger (RS) perturbation theory (PT), we construct ab initio approximations for the energy difference, the ...

In this paper we exploit the complementarity of inelastic neutron scattering (INS), infrared and Raman spectroscopies with ab initio calculations to generate an updated assignment of the vibrational modes of C(60). We have carried out periodic-DFT calculations of the high temperature face centred cubic phase modelled as the standard ...

We report a quantitative comparison of the interface structure of VN/MgO(001) using ab initio density-functional theory (DFT), aberration-corrected high-resolution transmission electron microscopy (HRTEM), and electron energy-loss spectroscopy (EELS). By HRTEM, we show an atomic resolution structure of epitaxially grown VN film on MgO ...

Folding and unfolding processes are important for the functional capability of polypeptides and proteins. In contrast with a physiological environment (solvated or condensed phases), an in vacuo study provides well-defined �clean room� conditions to analyze the intramolecular interactions that largely control the structure, stability, and folding or unfolding dynamics. Here we show that a ...

We explore an implementation of correlation-polarization interactions for electron scattering by polyatomic molecules. The short-range correlation is approximated by local and nonlocal density functional theory (DFT) models commonly used in quantum chemistry and solid-state physics. The long-range polarization is represented by general full tensor components. Furthermore, we ...

Using a systematic method, based on considering all possible hydrogen bond connections between two melamine molecules, and ab initio density functional theory (DFT) calculations, we consider the possible planar superstructures that the molecules can form in two dimensions. This is relevant to the assembly of melamine on flat metal ...

An ab initio density functional theory (DFT) study with correction for dispersive interactions was performed to study the adsorption of N2 and CO2 inside an (8, 8) single-walled carbon nanotube. We find that the approach of combining DFT and van der Waals correction is very effective for describing the long-range ...

We have generalized the approach for solving the multi-band Gutzwiller variational problem with density-density interaction to an arbitrary local interaction. The main advantage of our formulation is that it allows for a self-consistent numerical implementation which doesn't require any additional computational effort as compared to the simpler case of density-density interaction. Combined with ...

We use two fundamental theoretical frameworks to study the finite-size (shell) properties of the unitary gas in a periodic box: (1) an ab initio quantum Monte Carlo (QMC) calculation for boxes containing 4 to 130 particles provides a precise and complete characterization of the finite-size behavior, and (2) a new density functional theory ...

Two transition-metal oxide diatomic cations, VO{sup +} and MoO{sup +}, are considered in this article. Ground- and excited-state properties of the cations are derived from spin-polarized DF calculations, including spectroscopic constants and metal-oxygen bonding features. A set of ionization potentials are calculated and, for vanadium oxide, compared with photoelectron spectroscopy data and a few ...

This work provides an illustration that density functional theory (DFT) + U calculations may quantitatively describe transport phenomena in uranium dioxide. Oxygen diffusion mechanisms are investigated using both ab initio calculations and experimental approaches mainly involving self-diffusion coefficient measurements. The dependences ...

The partition coefficients (log P) of nucleoside analogs determined by the difference in the free energies of hydration and solvation in water-saturated octanol using the thermodynamic integration method are reported. The log P values calculated in this approach are closer to the experimental values compared to other ab initio methods. Solvation free ...

Using a recently developed first principles transport package, we study the electronic transport properties of Si films contacted to heavily doped n-type Si leads. The quantum transport analysis is carried out using density functional theory (DFT) combined with nonequilibrium Green's functions (NEGF). This particular combination of NEGF-DFT allows the ...

One of the grand challenges of superconductivity science is achieving a paradigm shift from discovery by serendipity to discovery by design. Empirical and heuristic rules have been a useful bridge in this desired direction. Many early superconductors were discovered by this method and by seredipity. DFT-based ab initio methods have ...

A very popular ab initio scheme to calculate electronic properties in solids is the use of hybrid functionals in density functional theory (DFT) that mixes a portion of the Fock exchange with DFT functionals. In spite of its success, a major problem still remains, related to the use of one single mixing parameter ...

An extensive scanning tunneling microscopy (STM) study of adsorption of submonolayer coverages of PTCDA molecules on the c(8�2) reconstructed InSb(001) surface is presented together with ab initio density functional theory (DFT) calculations. Our DFT calculations explain the variety of adsorption sites seen on ...

We have studied the mechanical compressibility and band structure of solid nitromethane both in equilibrium and compressed states using Hartree-Fock and density functional theory (DFT) with atom-centered all-electron linear combination of atomic orbitals basis sets. Hartree-Fock calculations with a 6-21G basis set, uncorrected for basis set superposition error, gave the best ...

A reaction scheme for the rearrangement of trimethylsilyl(methyl)silylene (Me3Si-Si-Me) discovered in a pioneering work of organosilicon chemistry (Wulff et al., J Am Chem Soc 1978, 100, 6236) was studied by the MP2 and DFT methods. We report a thermal reaction scheme for the rearrangement of Me3Si-Si-Me with the structures and energies of various silicon species along the ...

We propose a new long-range correction scheme that combines generalized-gradient-approximation (GGA) exchange functionals in density-functional theory (DFT) with the ab initio Hartree-Fock exchange integral by using the standard error function. To develop this scheme, we suggest a new technique that constructs an approximate ...

A systematic study of fluorenone and model oligofluorenes (trimer, pentamer, and heptamer) with a central keto defect was performed at ab initio Hartree-Fock (HF), density functional theory (DFT), configuration interaction singles (CIS), and time-dependent density functional theory (TD-DFT) levels. The main aim of ...

Using low energy electron diffraction (LEED), density functional theory (DFT) and scanning tunneling microscopy (STM), we have re-analyzed the Pd(100)-(5�5)R27� O surface oxide structure consisting, in the most recent model, of a strained PdO(1 0 1) layer on top of the Pd(1 0 0) surface [M. Todorova et al., Surf. Sci. 541 (2003) 101]. Both, DFT ...

The Fourier transform infrared and Fourier transform Raman spectra of isocyanic acid 1-naphthyl ester (C(11)H(7)NO) [ICANE] are recorded in solid phase, the harmonic vibrational frequencies, infrared intensities, Raman activities, bond length, bond angle and dihedral angle are calculated by HF and DFT methods by using different basis set. A detailed vibrational spectral ...

Prion protein, PrP, plays a causative role in several neurodegenerative diseases, including mad cow disease in cattle and Creutzfeldt-Jakob disease in humans. The PrP is known to efficiently bind copper ions and this ability has been linked to its function. PrP contains up to six binding sites, four of which are located in the so-called octarepeat region and are now well known. The binding sites ...

The results of density-functional theory (DFT) calculations of the energy barriers for three low-barrier relaxation processes in Ag/Ag(100) growth�edge-zipping, atom attraction, and downward funneling�are presented and compared with embedded atom method (EAM) calculations. In general, we find good agreement between the DFT values for these processes ...

We investigate the pressure-induced metal-insulator transition from diamond to ?-tin in bulk silicon, using quantum Monte Carlo (QMC) and density functional theory (DFT) approaches. We show that it is possible to efficiently describe many-body effects, using a variational wave function with an optimized Jastrow factor and a Slater determinant. Variational results are obtained ...

A direct an accurate technique for calculating the thermal X-ray absorption fine structure (XAFS) Debye-Waller factors (DWF) for materials of crystalline structure is presented. Using the Density Functional Theory (DFT) under the hybrid X3LYP functional, a library of MnO spin--optimized clusters are built and their phonon spectrum properties are calculated; these properties in ...

We present and discuss results of the density functional theory (DFT) for perfect UO(2) crystals with He atoms in octahedral interstitial positions therein. We have calculated basic bulk crystal properties and He incorporation energies into the low temperature anti-ferromagnetic UO(2) phase using several exchange-correlation functionals within the spin-polarized local density ...

FT-IR (4000-400 cm(-1)) and FT-Raman (3500-50 cm(-1)) spectral measurements of solid samples of 2-bromo-5-fluorobenzaldehyde (BFB) have been done. Ab initio (RHF/6-311G*) and DFT (B3LY/6-311G* and B3PW91/6-311G*) calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, depolarization ...

Ab initio calculations of the melting curve of molybdenum for the pressure range 0-400 GPa are reported. The calculations employ density functional theory (DFT) with the Perdew-Burke-Ernzerhof exchange-correlation functional in the projector augmented wave (PAW) implementation. Tests are presented showing that these techniques ...

The influence of changes in the contracted Gaussian basis set used for ab initio calculations of nuclear magnetic resonance (NMR) phosphorous chemical shift anisotropy (CSA) tensors was investigated. The isotropic chemical shitl and chemical shift anisotropy were found to converge with increasing complexity of the basis set at the Hartree-Fock @IF) level. ...

... Ab initio study on atomic structures and physical properties of CdSe quantum nanodots ... Figure 2. Diagram of covered nanodots. ...

... Title : Ab Initio Study on Atomic Structures and Physical Properties of CdSe Quantum Nanodots. Descriptive Note : Final rept. ...

... Accession Number : ADA270577. Title : Ab Initio Potential Energy Surface for the H + OCS Reaction. Descriptive Note : Final rept. ...