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 CH3CH(CH3)CH3 (Isobutane)

LSDA/6-311G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 2981 19 A1 2962  
2 A1 2908 4 A1 2904  
3 A1 2887 7 A1 2880  
4 A1 1434 -43 A1 1477  
5 A1 1346 -48 A1 1394  
6 A1 1150 -27 A1 1177  
7 A1 808 11 A1 797  
8 A1 416 -10 A1 426  
9 A2 2989 27 A2 2962  
10 A2 1394 -81 A2 1475  
11 A2 899 -67 A2 966  
12 A2 203 5 A2 198  
13 E 2991 29 E 2962  
14 E 2991 29 E 2962  
15 E 2974 12 E 2962  
16 E 2902 8 E 2894  
17 E 1429 -48 E 1477  
18 E 1402 -73 E 1475  
19 E 1322 -49 E 1371  
20 E 1285 -45 E 1330  
21 E 1151 -15 E 1166  
22 E 954 -12 E 966  
23 E 875 -43 E 918  
24 E 344 -23 E 367  
25 E 256   E    
The calculated vibrational frequencies were scaled by 0.9837

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.