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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 CCD/aug-cc-pVTZ
Calculated values were scaled by 0.957.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 torsion Au 84 -147 -231 -0.571
HCN+ hydrogen cyanide cation 2 Σ 1800 2604 804 0.691
CHONH2 formamide 12 torsion A" 289 22 -267 13.199
C3H6O Oxetane 18 B1 90 -43 -133 -2.098
C3O2 Carbon suboxide 7 Πu 61 -90 -151 -0.679
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 675 -2404 4.564
P(CH3)3 trimethylphosphine 22 E 259 197 -62 1.315
CO+ carbon monoxide cation 1 Σ 2184 2616 432 0.835
H2CS- thioformaldehyde anion 4 B1 450 287 -163 1.570
CN Cyano radical 1 Σ 2042 2579 537 0.792
C2H Ethynyl radical 2 Σ 1841 2301 461 0.800
C2H Ethynyl radical 3 torsion Π 372 749 378 0.496
CH2OH Hydroxymethyl radical 9 torsion A 234 393 159 0.596
HCCN cyanomethylene 5 Π 129 -375 -504 -0.344
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.644
CH2Cl chloromethyl radical 4 B1 402 -107 -509 -3.765
BF3+ boron trifluoride cation 5 B2 1791 3158 1368 0.567
HN3+ Hydrazoic acid cation 2 A' 1850 2827 977 0.654
O3 Ozone 3 B2 1042 1592 550 0.654
NO Nitric oxide 1 Σ 1876 2584 708 0.726
AsSe Arsenic monoselenide 1 Σ 280 423 143 0.662
VO Vanadium monoxide 1 Σ 1002 1891 890 0.530
SiC2 Silicon dicarbide 3 B2 196 -96 -292 -2.048
S3 Sulfur trimer 2 A1 281 597 316 0.471
SiH2D2 silane-d2 6 B1 2183 1568 -615 1.392
SiH2D2 silane-d2 8 B2 1601 2170 569 0.738
NH4 Ammonium radical 1 A1 2552 2963 411 0.861
Cl3- trichloride anion 2 Σu 327 191 -136 1.708
OPCl Phosphorus oxychloride 2 A' 308 491 183 0.628
OPCl Phosphorus oxychloride 3 A' 492 303 -189 1.624
F3- trifluoride anion 2 Σu 550 -214 -764 -2.566
H2POH Phosphinous acid 9 A" 375 256 -119 1.466
Mg2 Magnesium diatomic 1 Σg 48 26 -21 1.812
CHFCl Chlorofluoromethyl radical 6 A 540 398 -142 1.357
H2CNCN cyanamide, methylene 3 A' 2208 2982 774 0.741
H2CNCN cyanamide, methylene 4 A' 1621 2247 626 0.721
SNO Nitrogen oxide sulfide 1 A' 1527 497 -1030 3.074
ONNO NO dimer 2 A1 239 373 134 0.642
ONNO NO dimer 3 A1 135 321 187 0.419
ONNO NO dimer 4 torsion A2 117 216 99 0.541
ONNO NO dimer 6 B2 429 733 303 0.586