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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)=FULL/aug-cc-pVDZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2+ acetylene cation 5 Πu 837 680 -157 1.230
HCNO fulminic acid 5 torsion Π 224 -171 -395 -1.313
LiOH lithium hydroxide 3 Π 257 402 145 0.638
C2H- Ethynyl anion 3 Π 505 405 -100 1.246
C2H Ethynyl radical 3 torsion Π 372 -222 -594 -1.673
CH3 Methyl radical 2 torsion A2" 606 501 -105 1.210
CH2OH Hydroxymethyl radical 9 torsion A 234 428 194 0.547
NO2 Nitrogen dioxide 1 A1 1318 1082 -236 1.219
NO2 Nitrogen dioxide 2 A1 750 -1601 -2351 -0.469
NO2 Nitrogen dioxide 3 B2 1618 -740 -2358 -2.185
C3O Tricarbon monoxide 5 Π 109 -84 -193 -1.305
VO Vanadium monoxide 1 Σ 1002 1706 705 0.587
Li2O dilithium oxide 3 Πu 112 209 98 0.534
FO Oxygen monofluoride 1 Σ 1033 647 -385 1.595
C3 carbon trimer 3 Πu 63 -192 -256 -0.330
SiH2D2 silane-d2 6 B1 2183 1629 -554 1.340
SiH2D2 silane-d2 8 B2 1601 2252 651 0.711
H2OH2O water dimer 8 A' 103 157 54 0.658
H2OH2O water dimer 11 A" 108 165 57 0.654
H2OH2O water dimer 12 A" 88 143 55 0.617
H2COO Dioxymethyl radical 6 A' 908 679 -229 1.337