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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 HF/cc-pVQZ
Calculated values were scaled by 0.9084.

Species Name mode Symmetry Experiment Theory difference ratio
CHONH2 formamide 12 A" 289 170 -118 1.695
CH3NHCH3 Dimethylamine 24 A" 257 210 -47 1.224
C2H2N4 sym-tetrazine 18 B3u 254 370 116 0.686
NH2CN cyanamide 5 A' 408 614 206 0.665
C6H4 Benzyne 24 B2 472 299 -173 1.580
HCNO fulminic acid 5 Π 224 548 324 0.409
CH3NC methyl isocyanide 8 E 263 386 123 0.682
COBr2 Carbonic dibromide 4 B1 757 526 -231 1.439
COBr2 Carbonic dibromide 6 B2 512 359 -153 1.427
CH2D2 methane-d2 6 B1 3013 2184 -829 1.380
CH2D2 methane-d2 8 B2 2234 2949 715 0.758
C2H5 Ethyl radical 9 A' 528 425 -103 1.244
C2H Ethynyl radical 3 Π 372 555 184 0.669
C2H+ Ethynyl cation 3 Π 550 855 305 0.643
CH3 Methyl radical 2 A2" 606 373 -233 1.626
CH3 Methyl radical 2 A2" 606 373 -233 1.626
CH3 Methyl radical 2 A2" 606 373 -233 1.626
CH3 Methyl radical 2 A2" 606 373 -233 1.626
CH2OH Hydroxymethyl radical 8 A 482 699 217 0.689
CH2OH Hydroxymethyl radical 9 A 234 363 129 0.645
C2H3+ vinyl cation 2 A1 2217 2892 675 0.766
C2Cl2+ dichloroacetylene cation 4 Πg 318 461 143 0.690
C2Cl2+ dichloroacetylene cation 5 Πu 233 192 -41 1.216
FOOF Perfluoroperoxide 2 A 630 1043 413 0.604
FOOF Perfluoroperoxide 3 A 360 520 160 0.693
FOOF Perfluoroperoxide 5 B 614 1036 422 0.593
AsH3+ Arsine cation 2 A1 452 720 268 0.627
NS Mononitrogen monosulfide 1 Σ 1219 851 -368 1.432
SiN Silicon nitride 1 Σ 1151 881 -271 1.307
PS phosphorus sulfide 1 Σ 739 495 -245 1.494
CP Carbon monophosphide 1 Σ 1240 928 -312 1.336
SiH- silicon monohydride anion 1 Σ 2175 1739 -436 1.251
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SiH- silicon monohydride anion 1 Σ 2175 1739 -436 1.251
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SO+ sulfur monoxide cation 1 Σ 1360 888 -472 1.531
H3O+ hydronium 2 A1 954 757 -197 1.260
AlO Aluminum monoxide 1 Σ 979 730 -249 1.341
ClOO chloroperoxy radical 1 A' 1443 1099 -344 1.313
ClOO chloroperoxy radical 2 A' 414 705 291 0.587
ClOO chloroperoxy radical 3 A' 201 436 235 0.462
PN+ phosphorus nitride cation 1 Σ 1200 764 -436 1.570
GeH2 germylene 1 A1 1856 922 -934 2.013
H2POH Phosphinous acid 9 A" 375 262 -113 1.430
Mg2 Magnesium diatomic 1 Σg 51 2 -49 20.771
NNS Nitrogen sulfide 2 Σ 752 551 -201 1.365