National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release
NIST Standard Reference Database 101

I	Introduction
II	Experimental data
III	Calculated data
IV	Data comparisons
V	Cost comparisons
VI	Input and output files
VII	Tutorials and Units
VIII	Links to other sites
IX	Feedback
X	Older CCCBDB versions
XII	Geometries
XIII	Vibrations
XIV	Reaction data
XV	Entropy data
XVI	Bibliographic data
XVII	Ion data
XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

III.G.8.

Molecules sorted by size as determined by <r²> from HF/6-31G* calculation

Select one or more species by entering a chemical formula.

or choose by chemical groups.

Entering a formula will return all species with the same empirical formula. The characters * and ? can be used to indicate (0 or more) or (1 or more). For example C2H*F? will return all species with two C, zero or more H and one or more F and no other elements. A list of species that match the formula criteria is returned and one or more may be selected.

Going to the group selection page allows the selection of molecules with certain chemical groups, such as C=O bonds or NH2 groups. A list of species that match the group criteria is returned and one or more may be selected.