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 C4H5N (Pyrrole)

MP2/CEP-121G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3494 -37 A1 3531  
2 A1 3132 -17 A1 3149  
3 A1 3113 -15 A1 3128  
4 A1 1433 -39 A1 1472  
5 A1 1362 -39 A1 1401  
6 A1 1107 -41 A1 1148  
7 A1 1057 -17 A1 1075  
8 A1 997 -20 A1 1017  
9 A1 843 -39 A1 882  
10 A2 674 -190 A2 864  
11 A2 574 -118 A2 692  
12 A2 407 -207 A2 614  
13 B1 705 -122 B1 827  
14 B1 659 -63 B1 722  
15 B1 592 -29 B1 621  
16 B1 416 -59 B1 475  
17 B2 3127 -16 B2 3143  
18 B2 3103 -16 B2 3119  
19 B2 1478 -40 B2 1519  
20 B2 1415 -10 B2 1424  
21 B2 1242 -46 B2 1288  
22 B2 1117 -17 B2 1134  
23 B2 1016 -33 B2 1049  
24 B2 824 -41 B2 866  
The calculated vibrational frequencies were scaled by 0.9528

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.