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 C4H4N2 (Pyridazine)

MP2/CEP-121G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3084 21 A1 3063  
2 A1 3066 23 A1 3043  
3 A1 1519 -53 A1 1572  
4 A1 1397 -17 A1 1414  
5 A1 1222 -61 A1 1283  
6 A1 1113 -47 A1 1160  
7 A1 1027 -36 A1 1063  
8 A1 924 -40 A1 964  
9 A1 629 10 A1 619  
10 A2 841 -95 A2 936  
11 A2 811 -52 A2 863  
12 A2 433 -318 A2 751  
13 A2 217 -204 A2 421  
14 B1 832   B1   760 reassinged to mode 15
15 B1 715 -45 B1 760 696 questionable
16 B1 339 -31 B1 370  
17 B2 3075 -0 B2 3075  
18 B2 3060 17 B2 3043  
19 B2 1513 -52 B2 1565  
20 B2 1344 -100 B2 1444  
21 B2 1228 -11 B2 1239  
22 B2 1023 -29 B2 1052  
23 B2 996 -13 B2 1009  
24 B2 583 -81 B2 664  
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.