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

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CCCBDB Units and Tutorials

A. Choose Units

  1. Choose energy units
  2. Choose polarizability units polarizability
  3. Choose rotational constant units rotational constants
  4. Choose bond length units bond lengths
  5. Choose dipole and quadrupole units dipole quadrupole
  6. Choose moment of inertia units moments of inertia

B. Unit Explanations

  1. What's a hartree?
  2. What's a cm-1?
  3. What's a Debye?

C. Explanations

  1. Why scale vibrational frequencies?
  2. Internal rotation of a methyl group
  3. Calculating an Enthalpy of formation
  4. Vertical versus adiabatic ionzation energies.
  5. A glossary of computational terms.
  6. A brief description of the thermochemical quantities and methods.
  7. Two lectures on Extracting Thermochemical Information from ab Initio Data
    1. part 1
    2. part 2
  8. Calculating one angle when another is known in a symmetric molecule
  9. Contributions to entropy from different configurations
  10. The number of constants needed to specify the dipole or quadrupole in various point groups.
  11. Tutorial on Electric Quadrupole Moments (primitive, traceless, effective)
  12. Vibrational Zero-Point Energy
  13. Want other tutorials?

D. Forms for calculations and conversions

  1. Form for calculating an enthalpy of formation using a reaction
  2. Form for calculating the integrated heat capacity
  3. Form for converting between moments of inertia and rotational constants
  4. Perl script and information for computing ideal-gas thermodynamic functions from a Gaussian frequency calculation (From the NIST Chemical Informatics Research Group)

E. Reaction Suggestions

  1. Isodesmic reaction product suggestions
  2. You enter reactants and this page suggests products to form an isodesmic reaction.
  3. Suggestions for species with well defined experimental enthalpies of formation
  4. Binary decomposition search. Given "A" what are possible products "B" and "C" and their relative enthalpies.