return to home page

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

Compare vibrational frequencies in CCCBDB for C2H4 (Ethylene)

MP2/CEP-121G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3033 6 Ag 3026  
2 Ag 1588 -35 Ag 1623  
3 Ag 1330 -12 Ag 1342  
4 Au 1009 -14 Au 1023  
5 B1u 3007 18 B1u 2989 sym was B3U
6 B1u 1462 18 B1u 1444 sym was B3U
7 B2g 763 -176 B2g 940  
8 B2u 3137 33 B2u 3105  
9 B2u 812 -14 B2u 826  
10 B3g 3107 21 B3g 3086 sym was B1G
11 B3g 1215 -2 B3g 1217 sym was B1G
12 B3u 930 -20 B3u 949 sym was B1U
The calculated vibrational frequencies were scaled by 0.976

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.