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 QCISD(TQ)/6-31+G**
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 393 -219 1.556
HCN+ hydrogen cyanide cation 3 Π 760 1964 1204 0.387
HCNO fulminic acid 5 torsion Π 224 -255 -479 -0.880
C2H Ethynyl radical 3 torsion Π 372 165 -207 2.256
CH3 Methyl radical 2 torsion A2" 606 486 -120 1.247
CH2OH Hydroxymethyl radical 8 torsion A 482 717 235 0.673
CH2OH Hydroxymethyl radical 9 torsion A 234 448 214 0.522
OClO- Chlorine dioxide anion 2 A1 418 325 -93 1.287
AsSe Arsenic monoselenide 1 Σ 280 412 132 0.679
VO Vanadium monoxide 1 Σ 1002 -6742 -7743 -0.149
Li2O dilithium oxide 3 Πu 112 82 -30 1.361
FO Oxygen monofluoride 1 Σ 1033 661 -372 1.563
C3 carbon trimer 3 Πu 63 -135 -199 -0.468
S3 Sulfur trimer 2 A1 281 558 277 0.503
SiH2D2 silane-d2 6 B1 2183 1669 -514 1.308
SiH2D2 silane-d2 8 B2 1601 2309 708 0.693
CaS Calcium sulfide 1 Σ 459 362 -97 1.268
H2COO Dioxymethyl radical 6 A' 908 694 -214 1.308
CH2BH methyleneborane 6 B1 612 503 -109 1.216
ONNO NO dimer 4 torsion A2 117 179 62 0.652
SiH5+ Silane, protonated 1 A' 3694 4103 409 0.900