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Compare vibrational frequencies in CCCBDB for C2H4O4 (Formic acid dimer)

LSDA/6-311G**

18 11 26 13 55
Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency Scaled
Frequency
Harm.
diff
Fund.
diff
Symmetry Harmonic
Frequency
Fundamental
Frequency
Comment
1 Ag 2985 2949           
2 Ag 2063 2038   -911 Ag   2949 C-H was 2
3 Ag 1572 1553   -117 Ag   1670 C=O was 3
4 Ag 1439 1421   6 Ag   1415 C-O-H was 4
5 Ag 1368 1351   -24 Ag   1375 H-C-O was 5
6 Ag 1283 1268   54 Ag   1214 C-O was 6
7 Ag 706 697   20 Ag   677 O-C=O was 7
8 Ag 302 298           
9 Ag 178 176   39 Ag   137 ipb O-H.O was 9
10 Au 1242 1226   176 Au   1050 opb C-H was 13
11 Au 1023 1011   89 Au   922 opb O-H was 14
12 Au 217 214   46 Au   168 opb O-H.O was 15
13 Au 81 80   11 Au   69 twist was 16
14 Bg 1193 1179   119 Bg   1060 opb C-H was 10
15 Bg 1031 1018           
16 Bg 306 302   72 Bg   230 opb O-H.O was 12
17 Bu 2984 2947   -137 Bu   3084 O-H was 17
18 Bu 2297 2269   -669 Bu   2939 C-H was 18
19 Bu 1764 1742   -4 Bu   1746 C=O was 19
20 Bu 1472 1454   -0 Bu   1454 C-O-H was 20
21 Bu 1374 1357   -7 Bu   1364 H-C-O was 21
22 Bu 1325 1308   90 Bu   1218 C-O was 22
23 Bu 770 760   62 Bu   698 O-C=O was 23
24 Bu 450 444   176 Bu   268 O-H.O was 24
The calculated vibrational frequencies were scaled by 0.9877

See section Calculated; Vibrations; Scale Factors; Set scaling factors to change the scale factors used here.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to determine the least squares best scaling factor.
See section Calculated; Vibrations; Scale Factors; Scale factor uncertainty for information on where the above scaling factor is from.