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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IV.C.1. (XIII.D.1.)

Compare vibrational frequencies in CCCBDB for C5H5- (cylopentadienyl anion)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1   -3043 A1' 3043  
2   -983 A1' 983  
3   -1260 A2' 1260  
4   -710 A2" 710  
5   -3039 E1' 3039  
6   -1455 E1' 1455  
7   -1003 E1' 1003  
8   -625 E1" 625  
9   -3096 E2' 3096  
10   -1447 E2' 1447  
11   -1020 E2' 1020  
12   -854 E2' 854  
13   -686 E2" 686  
14   -600 E2" 600  
The calculated vibrational frequencies were scaled by 0.974

See section XIII.C.3 List or set vibrational scaling factors to change the scale factors used here.
See section III.B.3.c Calculate a vibrational scaling factor for a set of molecules to determine the least squares best scaling factor.
See section III.B.3.b List of vibrational scaling factors and their uncertainties for information on where the above scaling factor is from.