Theory and Computation
Contact: Mark Hybertsen
The CFN Theory and Computation Group supports an open community of staff, partners and users where theory interacts
vigorously with experiment to achieve fundamental advances in nanoscience, emphasizing opportunities for impact on future
energy needs. The staff members in the group have diverse areas of theoretical and phenomenological expertise. They are
actively engaged in research directed to fundamental understanding of phenomena in each of the CFN science themes as well
as research that advances materials theory capabilities. The staff members have collaborative research with external partners
and users, both theoretical and experimental. The facility supports and enables this research by providing computational
infrastructure, a suite of multipurpose software tools for materials theory, and methodological and theoretical consultation.
Associated Group Facilities
Group Members
- Mark Hybertsen, Physicist, Group Leader
Electronic structure methods; atomic scale structure, electronic states and optical properties of solids, surfaces and nanostructures; optoelectronic device physics.
- Ping Liu (joint appointment with BNL Chemistry), Associate Chemist
Atomic scale structure and reactivity of surfaces and nanostructures; heterogeneous catalytic processes; microkinetic modeling.
- Jim Davenport (jdaven@bnl.gov) (joint appointment with BNL CSC), Senior Physicist, Director Computational Sciences Center
Electronic structure methods; parallel computing; structure, electronic and magnetic properties of transition metal surfaces and nanostructures.
- James Muckerman (joint appointment with BNL Chemistry), Senior Chemist
Diverse quantum chemistry methods; chemical collision dynamics; homogeneous and heterogeneous catalytic processes.
Current Projects
Understand & Control of Catalytic Active Sites: New Nanocatalysts for the Water Gas Shift Reaction (Ping Liu)
Using DFT based calculations, we investigate the binding of reactants and intermediates to model catalyst structures and explore
reaction pathways. We are exploring promising transition metal nanoparticle catalysts on oxide supports as well as metal supported
oxide nanoparticle catalysts. This is done in close collaboration with the experimental catalysis programs in the BNL Chemistry
Department and with our CFN experimental colleagues.
Photocatalyzed Water Oxidation: The GaN/ZnO Alloy – Water Interface (Jim Muckerman)
The CFN Theory Group, in close collaboration with the BNL Chemistry Department and the Stony Brook University Physics Department, is
seeking to understand the semiconductor-water interface and the relationship to the catalytic process of water oxidation. Theoretical
challenges include identifying and treating the structural motifs where the reactions take place, accurate treatment of photoexcitations
in a heterogeneous system, and modeling the electron transfer processes. We are exploring the structure of the water interface with ZnO
and GaN surfaces. We plan to extend these studies to the mixed crystal surface and to include multiple layers of liquid water.
Metal-Organic Link Bonding Motifs: Reproducible Single Molecule Circuits (Mark Hybertsen)
In close collaboration the NSEC at Columbia University, we are exploring the bonding, structural and electronic properties of donor-acceptor
link motifs in the formation single molecule circuits. We have shown that amine, dimethyl phosphine and methyl sulfide linkages all support
reproducible electronic conductance signatures. We are currently investigating the systematic trends in conductance comparing these link
groups to understand the relative contributions of different electronic channels to the conductance.
Electronic Excitation Energies in Heterogeneous Nanosystems (Mark Hybertsen)
The GW approach to provides a remarkably balanced treatment of the electron correlation contribution to electronic excitation energies for a
broad range of materials. In particular, it includes the non-local polarization effects such as the well-known image potential that make an
essential contribution to excitation energies in heterogeneous nanosystems. For larger scale systems, the computational requirements quickly
grow beyond current capabilities. We are currently investigating approaches to the GW methodology that will enable the treatment of larger systems.
Last Modified: May 6, 2008
Please forward all questions about this site to:
Stephen Giordano.
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