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

Compare vibrational frequencies in CCCBDB for C4H6 (Cyclobutene)

MP2/CEP-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3071 11 A1 3060  
2 A1 2947 12 A1 2935  
3 A1 1524 -46 A1 1570  
4 A1 1448 -2 A1 1450  
5 A1 1178 -98 A1 1276  
6 A1 1088 -98 A1 1186  
7 A1 962 -151 A1 1113  
8 A1 877 -9 A1 886  
9 A2 3008 53 A2 2955  
10 A2 1123 -153 A2 1276  
11 A2 963 -118 A2 1081  
12 A2 866 16 A2 850  
13 A2 258 -67 A2 325  
14 B1 3021 66 B1 2955  
15 B1 1055 -19 B1 1074  
16 B1 839 -7 B1 846  
17 B1 620 -15 B1 635  
18 B2 3034 -13 B2 3047  
19 B2 2942 26 B2 2916  
20 B2 1423 -4 B2 1427  
21 B2 1258 -36 B2 1294  
22 B2 1157 -57 B2 1214  
23 B2 874 -14 B2 888  
24 B2 798 58 B2 740  
The calculated vibrational frequencies were scaled by 0.9494

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.