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XIII.F.2. (III.B.7.b.) (IV.C.7.) (XVIII.B.2.)

Bad vibrational frequency predictions

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 MP2FU/6-31G(2df,p)
Calculated values were scaled by 0.9423.

Species Name mode Symmetry Experiment Theory difference ratio
HCN+ hydrogen cyanide cation 2 Σ 1800 2704 904 0.666
C6H4O2 parabenzoquinone 30 B3u 109 89 -19 1.216
C2H4O3 trioxolane124 21 B 193 159 -34 1.214
CH2NN diazomethane 6 B1 406 131 -275 3.093
NH2CN cyanamide 5 A' 408 634 226 0.644
COBr2 Carbonic dibromide 6 B2 512 348 -164 1.469
CO+ carbon monoxide cation 1 Σ 2214 2692 478 0.822
CH2CHO Vinyloxy radical 10 A" 703 1028 325 0.684
O2+ diatomic oxygen cation 1 Σg 1906 1422 -484 1.340
AsF5 Arsenic pentafluoride 7 E' 123 101 -22 1.224
CaOH Calcium monohydroxide 2 Σ 353 616 263 0.573
CaOH Calcium monohydroxide 3 Π 609 372 -237 1.636
Cu2 Copper dimer 1 Σg 265 417 153 0.634
NCO isocyanato radical 1 Σ 1921 2341 420 0.821
GeH2 germylene 1 A1 1856 946 -910 1.962
ZnCH3 Zinc monomethyl 6 E 315 598 283 0.527
ZnCN Zinc monocyanide 3 Π 212 174 -38 1.219
ZnH2 Zinc hydride 3 Πu 633 523 -109 1.209
GeH2 germylene 2 A1 916 2009 1093 0.456
HCN+ hydrogen cyanide cation 1 Σ 3050 3531 481 0.864
C4H6O2 2,3-Butanedione 9 Ag 614 505 -109 1.217
C4H6O2 2,3-Butanedione 21 Bg 240 127 -113 1.896
COBr2 Carbonic dibromide 4 B1 757 526 -231 1.440
C2F2 difluoroacetylene 4 Πg 270 453 183 0.596
C2H+ Ethynyl cation 3 Π 550 810 260 0.679
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.267
CaF2 Calcium difluoride 2 A1 120 84 -36 1.428
N2O3 Dinitrogen trioxide 9 A" 63 169 106 0.372
PN+ phosphorus nitride cation 1 Σ 1200 1607 407 0.747
CBr2F2 Methane, dibromodifluoro- 3 A1 140 346 206 0.404
CBr2F2 Methane, dibromodifluoro- 9 B2 235 337 102 0.698
C4H6O2 2,3-Butanedione 13 Au 1111 920 -191 1.207