National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

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

Compare vibrational frequencies in CCCBDB for C4H6 (Methylenecyclopropane)

QCISD/6-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3016 6 A1 3010  
2 A1 3003 1 A1 3002  
3 A1 1785 42 A1 1743  
4 A1 1460 23 A1 1437  
5 A1 1414 4 A1 1410  
6 A1 1046 10 A1 1036  
7 A1 1029 27 A1 1002  
8 A1 726 3 A1 723  
9 A2 3070 19 A2 3051  
10 A2 1145 1 A2 1144  
11 A2 933 -4 A2 937  
12 A2 602 -14 A2 616  
13 B1 3081 10 B1 3071  
14 B1 1075 3 B1 1072  
15 B1 865 -24 B1 889  
16 B1 744 -4 B1 748  
17 B1 271 -89 B1 360  
18 B2 3093 7 B2 3086  
19 B2 2999 0 B2 2999  
20 B2 1428 75 B2 1353  
21 B2 1122 -52 B2 1174  
22 B2 1059 -66 B2 1125  
23 B2 888 96 B2 792  
24 B2 342 52 B2 290  
The calculated vibrational frequencies were scaled by 0.9523

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.