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

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

MP2/3-21G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1' 2939 23 A1' 2916  
2 A1' 2181 -59 A1' 2240  
3 A1' 1434 54 A1' 1380  
4 A1' 657 -68 A1' 725  
5 A1" 7        
6 A2" 2940 2 A2" 2938  
7 A2" 1426 44 A2" 1382  
8 A2" 1071 -81 A2" 1152  
9 E' 3000 27 E' 2973  
10 E' 1519 63 E' 1456  
11 E' 1079 25 E' 1054  
12 E' 175 -38 E' 213  
13 E" 3000 34 E" 2966  
14 E" 1517 69 E" 1448  
15 E" 1050 21 E" 1029  
16 E" 192 -179 E" 371  
The calculated vibrational frequencies were scaled by 0.9545

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.