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

Compare vibrational frequencies in CCCBDB for C4H6 (Methylenecyclopropane)

MP2/6-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3018 8 A1 3010  
2 A1 3005 3 A1 3002  
3 A1 1765 22 A1 1743  
4 A1 1453 16 A1 1437  
5 A1 1409 -1 A1 1410  
6 A1 1037 1 A1 1036  
7 A1 1021 19 A1 1002  
8 A1 726 3 A1 723  
9 A2 3081 30 A2 3051  
10 A2 1138 -6 A2 1144  
11 A2 935 -2 A2 937  
12 A2 599 -17 A2 616  
13 B1 3091 20 B1 3071  
14 B1 1068 -4 B1 1072  
15 B1 855 -34 B1 889  
16 B1 739 -9 B1 748  
17 B1 264 -96 B1 360  
18 B2 3107 21 B2 3086  
19 B2 3002 3 B2 2999  
20 B2 1422 69 B2 1353  
21 B2 1112 -62 B2 1174  
22 B2 1044 -81 B2 1125  
23 B2 886 94 B2 792  
24 B2 339 49 B2 290  
The calculated vibrational frequencies were scaled by 0.943

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.