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)

MP2/LANL2DZ

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3018 8 A1 3010  
2 A1 3016 14 A1 3002  
3 A1 1731 -12 A1 1743  
4 A1 1459 22 A1 1437  
5 A1 1428 18 A1 1410  
6 A1 1071 35 A1 1036  
7 A1 974 -28 A1 1002  
8 A1 667 -56 A1 723  
9 A2 3108 57 A2 3051  
10 A2 1141 -3 A2 1144  
11 A2 952 15 A2 937  
12 A2 618 2 A2 616  
13 B1 3121 50 B1 3071  
14 B1 1081 9 B1 1072  
15 B1 837 -52 B1 889  
16 B1 756 8 B1 748  
17 B1 262 -98 B1 360  
18 B2 3121 35 B2 3086  
19 B2 3012 13 B2 2999  
20 B2 1437 84 B2 1353  
21 B2 1112 -62 B2 1174  
22 B2 1094 -31 B2 1125  
23 B2 858 66 B2 792  
24 B2 334 44 B2 290  
The calculated vibrational frequencies were scaled by 0.9631

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.