National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
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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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.

XIII.

Vibration data

1. Experimental
1. Experimental vibrational data for a given species.
2. Calculated
1. Calculated vibrational data.
2. Vibrational zero-point energies
3. Compare two model chemistries
4. View animated vibrations
5. Anharmonic Vibrational Frequency calculations
3. Vibrational Frequency scaling factors
1. List factors.
2. List factors and uncertainties.
3. Set vibrational scaling factors.
4. Explanation of vibrational scaling factors
5. Calculate a vibrational scaling factor for a given set of molecules.
4. Comparisons
1. Compare Vibrational frequencies for a given molecule.
2. Compare one particular vibrational frequency for a given molecule.
3. Compare vibrational zero point energies
4. Compare vibrational intensities for a particular vibrational mode
5. Compare two model chemistries
6. Compare vibrational frequency differences
7. Compare anharmonic constants for triatomics
5. Lookup
1. Lookup molecules by their calculated vibrational frequencies.
6. Poor results
1. Bad predicted vibrational frequencies based on comparing HF and MP2 calculations.
2. Bad predicted vibrational frequencies based on differences and ratios with experimental frequencies
3. Bad predicted vibrational frequencies based on anharmonic constants
7. Explanations
1. Why scale vibrational frequencies?
2. What's a cm^-1?
3. Vibrational Zero-Point Energy