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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 QCISD(TQ)/aug-cc-pVDZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 366 -246 1.673
HCN+ hydrogen cyanide cation 3 Π 760 4284 3524 0.177
C4H2 Diacetylene 7 Πg 482 -663 -1145 -0.727
C4H2 Diacetylene 8 Πu 630 499 -131 1.263
C4H2 Diacetylene 9 Πu 231 113 -118 2.053
HCNO fulminic acid 5 torsion Π 224 -209 -433 -1.074
C2H- Ethynyl anion 3 Π 505 397 -108 1.272
C2H Ethynyl radical 3 torsion Π 372 -254 -625 -1.465
CH3 Methyl radical 2 torsion A2" 606 499 -108 1.216
CH2OH Hydroxymethyl radical 9 torsion A 234 428 194 0.546
OClO- Chlorine dioxide anion 2 A1 418 317 -101 1.319
C3O Tricarbon monoxide 5 Π 109 -90 -199 -1.214
AsSe Arsenic monoselenide 1 Σ 280 404 124 0.692
VO Vanadium monoxide 1 Σ 1002 -5613 -6615 -0.178
FO Oxygen monofluoride 1 Σ 1033 643 -390 1.606
C3 carbon trimer 3 Πu 63 -186 -249 -0.341
S3 Sulfur trimer 2 A1 281 548 267 0.513
SiH2D2 silane-d2 6 B1 2183 1612 -571 1.354
SiH2D2 silane-d2 8 B2 1601 2229 628 0.718
H2OH2O water dimer 12 A" 88 137 49 0.640
H2COO Dioxymethyl radical 6 A' 908 678 -230 1.340
ONNO NO dimer 3 A1 135 206 71 0.653
ONNO NO dimer 4 torsion A2 117 208 91 0.563