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IV.C.1. (XIII.D.1.)

Compare vibrational frequencies in CCCBDB for H2CCCCH2 (Butatriene)

QCISD/3-21G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 2989 -6 Ag 2995  
2 Ag 2060 -19 Ag 2079  
3 Ag 1476 46 Ag 1430  
4 Ag 840 -38 Ag 878  
5 Au 734 -2 Au 736  
6 B1u 2990 -4 B1u 2994  
7 B1u 1574 -34 B1u 1608  
8 B1u 1411 41 B1u 1370  
9 B2g 872 -6 B2g 878 assumed under nu4
10 B2g 297 -247 B2g 544 moved from nu9 moved from nu9
11 B2u 3058 -22 B2u 3080  
12 B2u 1064 4 B2u 1060  
13 B2u 196 -19 B2u 215  
14 B3g 3057 -2 B3g 3059  
15 B3g 1046   B3g   663 questionable
16 B3g 259 -71 B3g 330  
17 B3u 878 24 B3u 854  
18 B3u 180 -35 B3u 215 asssumed from nu13
The calculated vibrational frequencies were scaled by 0.9611

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.