National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 22May 2022
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

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IV.

Data comparisons

A.Comparisons of Enthalpies
1.User specified reaction at 0K.
a.User specified reaction at 298K.
2. Atomization enthalpies.
a. Atomization enthalpies at 298K.
3.Methods which provide Enthalpy of formation directly enthalpy of formation
a. Compare two semi-empirical methods.
b.Compare semi-empirical and group additivity methods.
4.Relative enthaplies of isomers
a.Compare sets of isomers.
b.Compare sets of tautomers.
5.Barriers to internal rotation internal rotation
B.Comparison of Entropies entropy
1.Entropies for a given molecule entropy
2.Reaction Entropies at 298K
3.Heat Capacities (Cp) at 298K heat capacity
4.Entropies for a selection of molecules entropy
5.Integrated heat capacities integrated heat cpacity
C.Comparison of Vibrations vibrations
1.Vibrational frequencies for a given molecule.
2.One particular vibrational frequency for a given molecule.
3.Calculate a vibrational scaling factor for a given set of molecules.
4.Notes on vibrational scaling factors
5.Vibrational zero point energies vibrational zero point energy
6.Vibrational intensities for a given mode
7.Poorly predicted vibrational frequencies
8.Anharmonic vibrational frequencies for a given molecule
D.Comparison of Geometries
1.Bonds, angles, or dihedrals for a given molecule. bond lengths bond angles
2.Rotational constants for a given molecule. rotational constants
3.Point Groups
a.list molecules whose point groups differ from experiment
4.Bond or angle type for several molecules.
5.Products of Moments of Inertia. moments of inertia
6.Bad calculated geometries. badmoment of inertia
7.Bad calculated bond lengths badbond lengths
8.Average bond length differences by model chemistrybond lengths
E.Electrostatic Properties Comparisons
1.Electric dipoles. dipole
2.Koopmans' theorem ionization energy predictions for a single species. ioniztion energy
3.Koopmans' theorem ionization energy predictions across a selection of species. ioniztion energy
4.Polarizabilities. polarizability
5.Quadrupole moments. quadrupole
6.Ionization Energy. ionization energy
7.Electron Affinity. electron affinity
8.Proton Affinity.