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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 3014 19 Ag 2995  
2 Ag 2078 -1 Ag 2079  
3 Ag 1488 58 Ag 1430  
4 Ag 847 -31 Ag 878  
5 Au 740 4 Au 736  
6 B1u 3015 21 B1u 2994  
7 B1u 1588 -20 B1u 1608  
8 B1u 1423 53 B1u 1370  
9 B2g 880 2 B2g 878 assumed under nu4
10 B2g 300 -244 B2g 544 moved from nu9 moved from nu9
11 B2u 3083 3 B2u 3080  
12 B2u 1073 13 B2u 1060  
13 B2u 197 -18 B2u 215  
14 B3g 3083 24 B3g 3059  
15 B3g 1054   B3g   663 questionable
16 B3g 261 -69 B3g 330  
17 B3u 885 31 B3u 854  
18 B3u 182 -33 B3u 215 asssumed from nu13
The calculated vibrational frequencies were scaled by 0.9692

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.