return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

19 02 11 15 45

Calculated frequencies that differ from experiment by more than 400 cm-1 or have a ratio with experiment outside of 0.7 to 1.2 are listed

Calculated vibrational frequencies ("theory" in table) are calculated at CCSD/aug-cc-pVQZ
Calculated values were scaled by 0.9534.

Species Name mode int rot Symmetry Experiment Theory difference ratio
AsSe Arsenic monoselenide 1 Σ 280 407 127 0.688
SiC2 Silicon dicarbide 3 B2 196 126 -70 1.555
C3 carbon trimer 3 Πu 63 -57 -120 -1.119
S3 Sulfur trimer 2 A1 281 598 317 0.470
SiH2D2 silane-d2 6 B1 2183 1563 -620 1.397
SiH2D2 silane-d2 8 B2 1601 2162 561 0.740
Br3- tribromide anion 2 Σu 214 159 -55 1.348
OPCl Phosphorus oxychloride 2 A' 308 492 184 0.626
OPCl Phosphorus oxychloride 3 A' 492 305 -187 1.616
H2POH Phosphinous acid 9 A" 375 257 -118 1.459
Mg2 Magnesium diatomic 1 Σg 48 26 -22 1.826