National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
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 C2H4+ (Ethylene cation)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3008        
2 Ag 1532 44 Ag 1488  
3 Ag 1243 -16 Ag 1259  
4 Au 347 263 Au 84  
5 B1u 2998        
6 B1u 1431        
7 B2g 1089 187 B3u 901  
8 B2u 3125 2022 B2g 1103  
9 B2u 811        
10 B3g 3110 2297 B2u 813  
11 B3g 1203 -1776 B1u 2979  
12 B3u 987 -424 B1u 1412  
The calculated vibrational frequencies were scaled by 0.9106

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.