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

Compare vibrational frequencies in CCCBDB for C4H6 (Cyclobutene)

MP2/CEP-121G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3071 11 A1 3060  
2 A1 2938 3 A1 2935  
3 A1 1512 -58 A1 1570  
4 A1 1453 3 A1 1450  
5 A1 1185 -91 A1 1276  
6 A1 1088 -98 A1 1186  
7 A1 969 -144 A1 1113  
8 A1 870 -16 A1 886  
9 A2 2990 35 A2 2955  
10 A2 1113 -163 A2 1276  
11 A2 985 -96 A2 1081  
12 A2 824 -26 A2 850  
13 A2 267 -58 A2 325  
14 B1 3003 48 B1 2955  
15 B1 1056 -18 B1 1074  
16 B1 836 -10 B1 846  
17 B1 619 -16 B1 635  
18 B2 3043 -4 B2 3047  
19 B2 2932 16 B2 2916  
20 B2 1431 4 B2 1427  
21 B2 1262 -32 B2 1294  
22 B2 1172 -42 B2 1214  
23 B2 873 -15 B2 888  
24 B2 805 65 B2 740  
The calculated vibrational frequencies were scaled by 0.9528

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.