return to home page

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' 2929 13 A1' 2916  
2 A1' 2173 -67 A1' 2240  
3 A1' 1429 49 A1' 1380  
4 A1' 655 -70 A1' 725  
5 A1" 7        
6 A2" 2930 -8 A2" 2938  
7 A2" 1422 40 A2" 1382  
8 A2" 1068 -84 A2" 1152  
9 E' 2990 17 E' 2973  
10 E' 1513 57 E' 1456  
11 E' 1075 21 E' 1054  
12 E' 174 -39 E' 213  
13 E" 2990 24 E" 2966  
14 E" 1512 64 E" 1448  
15 E" 1046 17 E" 1029  
16 E" 191 -180 E" 371  
The calculated vibrational frequencies were scaled by 0.9513

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.