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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 ?a 1151 -1811 A1 2962  
2 ?a 1151 -1753 A1 2904  
3 ?a 1150 -1730 A1 2880  
4 A1 2981 1504 A1 1477  
5 A1 2908 1514 A1 1394  
6 A1 2887 1710 A1 1177  
7 A1 1434 637 A1 797  
8 A1 1346 920 A1 426  
9 A1 808 -2154 A2 2962  
10 A1 416 -1059 A2 1475  
11 A2 2989 2023 A2 966  
12 A2 1394 1196 A2 198  
13 A2 899 -2063 E 2962  
14 A2 203 -2759 E 2962  
15 E 2991 29 E 2962  
16 E 2974 80 E 2894  
17 E 2902 1425 E 1477  
18 E 1429 -46 E 1475  
19 E 1402 31 E 1371  
20 E 1322 -8 E 1330  
21 E 1285 119 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.