National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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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I.B.3. (II.A.2.)

All data (experiment and calculated) in the CCCBDB for C5H5- (cylopentadienyl anion)

Other names
cyclopentadienide anion; cyclopentadienide; cyclopenta-2,4-dien-1-ide;

An "x" indicates that data is available. A number indicates how many calculations have been completed.
Property Experiment Calculated Comparison
Enthalpy 298.15K enthalpy of formation      
Enthalpy 0K enthalpy of formation      
Energy 0K   234  
Energy 298.15K   198  
Atomization Enthalpy 298.15K  5 
Atomization Enthalpy 0K  179 
Entropy (298.15K) entropy  180 
Entropy at any temperature   180  
Integrated Heat Capacity integrated heat capacity  180 
Heat Capacity (Cp) Heat capacity  180 
Nuclear Repulsion Energy   226  
HOMO-LUMO Energies HOMO energies   227  
Barriers to Internal Rotation internal rotation  0 
Geometries Cartesians  216  
Internal Coordinates bond lengths bond angles  216 
Products of moments of inertia moments of inertia  219 
Rotational Constants rotational constants  227 
Point Group  228 
Vibrations Vibrational Frequencies vibrations x5424x
Vibrational Intensities  222 
Zero-point energies x226x
Vibrational scaling factors x
Anharmonic frequencies and constants      
Electronic States Electronic states x 0  
Electrostatics Atom charges   114  
Dipole dipole  137 
Quadrupole quadrupole  134 
Polarizability polarizability  138 
Other results Spin   0  
Number of basis functions   4  
Conformations   1  
2015 06 10 17:36