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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(T)=FULL/aug-cc-pVTZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
HCN+ hydrogen cyanide cation 3 Π 760 1815 1055 0.419
CHSNH2 thioformamide 12 A" 393 296 -97 1.326
CH2CCH2 allene 1 A1 3015 1086 -1929 2.776
CH2CCH2 allene 8 E 3086 1490 -1596 2.071
HCNO fulminic acid 5 torsion Π 224 -114 -338 -1.966
H2CS- thioformaldehyde anion 4 B1 450 324 -126 1.390
SiF2+ Silicon difluoride cation 2 A1 350 285 -65 1.230
CFCl2 dichlorofluoromethyl radical 2 A' 747 619 -128 1.206
CH3 Methyl radical 2 torsion A2" 606 487 -120 1.246
CH2OH Hydroxymethyl radical 9 torsion A 234 422 188 0.555
HCCN cyanomethylene 5 Π 129 -349 -478 -0.369
CHCl2 dichloromethyl radical 4 A' 190 302 112 0.629
CH2Cl chloromethyl radical 4 B1 402 62 -340 6.524
NF3 Nitrogen trifluoride 1 A1 1032 669 -363 1.543
NF3 Nitrogen trifluoride 2 A1 647 1054 407 0.614
NF3 Nitrogen trifluoride 3 E 907 513 -394 1.769
NF3 Nitrogen trifluoride 4 E 492 926 434 0.531
AsSe Arsenic monoselenide 1 Σ 280 428 148 0.655
C3 carbon trimer 3 Πu 63 102 39 0.621
C4 Carbon tetramer 5 Πu 160 109 -51 1.462
S3 Sulfur trimer 2 A1 281 582 301 0.483
SiH2D2 silane-d2 6 B1 2183 1634 -549 1.336
SiH2D2 silane-d2 8 B2 1601 2260 659 0.708
NH4 Ammonium radical 1 A1 2552 3076 524 0.830
BH3PH3 borane phosphine 12 E 447 359 -88 1.243
OPCl Phosphorus oxychloride 2 A' 308 504 196 0.611
OPCl Phosphorus oxychloride 3 A' 492 305 -187 1.615
H2OH2O water dimer 8 A' 103 153 50 0.673
H2OH2O water dimer 12 A" 88 134 46 0.655
CHFCl Chlorofluoromethyl radical 6 A 540 409 -131 1.319
H2CNCN cyanamide, methylene 3 A' 2208 3104 896 0.711
H2CNCN cyanamide, methylene 4 A' 1621 2266 645 0.715
SNO Nitrogen oxide sulfide 3 A' 792 506 -286 1.566
ONNO NO dimer 3 A1 135 258 124 0.521
ONNO NO dimer 4 torsion A2 117 220 103 0.532
ONNO NO dimer 6 B2 429 619 190 0.694
AlNC Aluminum isocyanide 3 Π 100 171 71 0.583