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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Select group of species

Select from the following tables to search for the species of interest. The search performs a boolean AND so that if both C-N bond is selected and C-F bond is selected the search will return only species with both C-N and C-F bonds. "#" indicates a triple bond.

A-H bonds   C-A bonds   Other
C-H Si-H   CC any CN any CO any CS any CX any   N-O
N-H P-H   C-C C-N C-O C-S C-F   N-S
O-H S-H   C=C C=N C=O C=S C-Cl   C-P
          C#C C#N        C-Br   S-O

Organic Groups
alkane C-O-H alcohol r-N=O OOH peroxy 3 membered ring
alkene C-O-C ether r-NO2 nitro NH2 amine 4 membered ring
alkyne COOH acid r-ONO nitrite     5 membered ring
diene C(O)OC ester r-ONO2 nitrate RCH3 6 membered ring
    CC(O)C ketone C(O)N amide R2CH2 aromatic
    CC(O)H aldehyde     R3CH bicyclic
    COC epoxide     R4C phenyl
    Chalcogen (O, S, Se, Te) Halogen (F, Cl, Br, I)
substituted methanes, etc.
methanes ethanes propanes butanes pentanes
   ethenes         hexanes

Must contain these elements
Must NOT contain these elements
only first row (H thru Ne)
contains a metal

Atom Count
Total number of atoms
Heavy (non-hydrogen) atoms

Radicals radical Ions Hydrogen-bonded Salts
Must be a radical (unpaired electrons) Must be an ion (charged) Hydrogen-bonded dimer Must be a salt
Exclude all radicals Exclude all ions    Exclude all salts

Atmospheric Refrigerants
Atmospheric molecules CFC HCFC HBFC HFC PFC

Point Group
C1 Cs Ci C∞v D∞h Td Oh Kh
C2 C3
C2v C3v C4v
C2h C3h
D2 D3
D2d D3d D4d D5d
D2h D3h D5h D6h D7h

Experimental Uncertainty in Enthalpy of formation (kJ/mol)
Less or equal to kJ/mol More than kJ/mol

G2 Set (no ions, no excited states)
G2-1 set (53 species)
G2/97 set extended (146 species)

Constraints from experimental vibrational frequencies
experimental frequencies are present
species that are good for determining scaling factors