Search for Species Data by Proton
Affinity Value
Please follow the steps below to
conduct your search (Help):
- You may search for species based on proton affinity
values in two ways:
- Specify a single value; the system will search for
values within 5.0 kJ/mol (1.2 kcal/mol) of this value.
- Specify a range. The limits of the range should
be separated by a comma.
- The units used for displaying data will be the
same ones used to specify the value.
Rules for formula restriction (step 2)
(Back to search)
A chemical formula may be entered to restrict the search to
species which match the formula. The manner in which the
formula is interpreted is controlled by two checkboxes below
the formula entry box:
- Allow elements not specified in formula
- When checked, this option indicates that species
containing elements not specified in the formula
will also be matched. For example, a search for
C2 will match all of the species which
contain exactly two carbon atoms and any number of
other atoms.
- Allow more atoms of elements in formula than specified
- This option indicates that species containg more
atoms than specified of a given element will be matched.
For example, a search for HC with only
this option checked will match only hydrocarbons.
- If one or more of the data types are checked,
the search will be restricted to species which
contain at least one of the data types specified.
- If none of the data types are checked, there
will be no restrictions on the search.
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