National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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 C4H4N2 (Pyridazine)

PBEPBE/6-31G(2df,p)

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3104 41 A1 3063  
2 A1 3071 28 A1 3043  
3 A1 1544 -28 A1 1572  
4 A1 1418 4 A1 1414  
5 A1 1177 -106 A1 1283  
6 A1 1121 -39 A1 1160  
7 A1 1055 -8 A1 1063  
8 A1 978 14 A1 964  
9 A1 648 29 A1 619  
10 A2 975 39 A2 936  
11 A2 909 46 A2 863  
12 A2 755 4 A2 751  
13 A2 343 -78 A2 421  
14 B1 939   B1   760 reassinged to mode 15
15 B1 731 -29 B1 760 696 questionable
16 B1 337 -33 B1 370  
17 B2 3089 14 B2 3075  
18 B2 3067 24 B2 3043  
19 B2 1538 -27 B2 1565  
20 B2 1370 -74 B2 1444  
21 B2 1256 17 B2 1239  
22 B2 1043 -9 B2 1052  
23 B2 1013 4 B2 1009  
24 B2 599 -65 B2 664  
The calculated vibrational frequencies were scaled by 0.9897

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.