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

Compare vibrational frequencies in CCCBDB for CH3CCCH3 (2-Butyne)

QCISD/3-21G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1' 2930 14 A1' 2916  
2 A1' 2259 19 A1' 2240  
3 A1' 1438 58 A1' 1380  
4 A1' 661 -64 A1' 725  
5 A1" 5        
6 A2" 2930 -8 A2" 2938  
7 A2" 1431 49 A2" 1382  
8 A2" 1067 -85 A2" 1152  
9 E' 2984 11 E' 2973  
10 E' 1519 63 E' 1456  
11 E' 1079 25 E' 1054  
12 E' 182 -31 E' 213  
13 E" 2984 18 E" 2966  
14 E" 1518 70 E" 1448  
15 E" 1055 26 E" 1029  
16 E" 290 -81 E" 371  
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.