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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 QCISD/6-31G**
Calculated values were scaled by 0.9414.

Species Name mode Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 438 -174 1.397
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 54 -21 1.388
CH3COOCH3 methyl acetate 27 A" 110 70 -40 1.570
C6H5CHO benzaldehyde 32 A" 688 537 -151 1.281
C6H4O2 parabenzoquinone 12 B1u 1354 3070 1716 0.441
C6H4O2 parabenzoquinone 30 B3u 109 81 -27 1.336
C3H6O 2-Propen-1-ol 21 A 554 426 -129 1.302
C6H5Cl chlorobenzene 18 B1 685 530 -155 1.292
C3H2N2 Malononitrile 6 A1 167 136 -31 1.229
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 158 -35 1.219
C5H8 Cyclopentene 18 A' 254 159 -95 1.593
C2H4O3 trioxolane124 21 B 193 159 -34 1.217
C6H5F Fluorobenzene 18 B1 685 530 -155 1.292
C2H3NO3 Oxamic acid 21 A" 162 42 -120 3.889
C6H4F2 1,4-difluorobenzene 16 B2g 692 514 -178 1.346
C5H8 1,4-Pentadiene 16 A 137 283 146 0.483
C6H10 1,5-Hexadiene 14 Ag 351 259 -92 1.355
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 180 -37 1.206
GeO2 Germanium dioxide 3 Πu 196 150 -45 1.300
NaOH sodium hydroxide 3 Π 300 99 -201 3.029
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.604
C2H5 Ethyl radical 9 A' 528 436 -92 1.212
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 856 -280 1.327
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 117 -147 2.248
C2Cl2 dichloroacetylene 4 Πg 333 178 -155 1.874
AsH3+ Arsine cation 2 A1 452 661 209 0.684
Li2O dilithium oxide 3 Πu 112 42 -69 2.647
CaOH Calcium monohydroxide 3 Π 609 378 -231 1.611
CH3COCH3 Acetone 12 A2 77 49 -28 1.575
C2H6O2S Dimethyl sulfone 20 B1 262 210 -52 1.249
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 307 93 0.698
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.263
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 519 -113 1.217
C6H5NO2 Nitrobenzene 22 B1 675 521 -154 1.297
C6H4O2 parabenzoquinone 3 Ag 1667 3088 1421 0.540
C6H4O2 parabenzoquinone 5 Ag 770 1605 835 0.480
C6H4O2 parabenzoquinone 14 B1u 728 1330 602 0.547
C6H4O2 parabenzoquinone 22 B2u 408 1042 634 0.392
C4H8O Furan, tetrahydro- 33 B 137 44 -93 3.136
CH2OH Hydroxymethyl radical 8 A 482 711 229 0.678
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.367
BrF5 bromine pentafluoride 6 B2 281 220 -61 1.278
C3 carbon trimer 3 Πu 63 47 -17 1.354
CaOH Calcium monohydroxide 2 Σ 353 599 246 0.589
C4 Carbon tetramer 4 Πg 323 252 -71 1.282
GeH2 germylene 1 A1 1856 915 -941 2.029
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.530
C3H3NO Isoxazole 14 A" 1033 848 -185 1.218
C4H4N2 Pyridazine 13 A2 421 341 -80 1.233
NH2CN cyanamide 5 A' 408 636 228 0.642
C2H3NO3 Oxamic acid 16 A" 984 758 -226 1.298
C2H3NO3 Oxamic acid 18 A" 745 595 -150 1.252
COBr2 Carbonic dibromide 6 B2 512 327 -185 1.568
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.676
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 330 -126 1.384
C5H8 1,3-Pentadiene, (E)- 31 A" 361 234 -127 1.543
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 85 -273 4.191
C2Cl2+ dichloroacetylene cation 5 Πu 233 166 -67 1.404
BF3+ boron trifluoride cation 4 E' 411 -1046 -1457 -0.393
ZnCN Zinc monocyanide 3 Π 212 80 -132 2.637
PCl5 Phosphorus pentachloride 2 A1' 370 276 -94 1.342
CuH Copper monohydride 1 Σ 1941 613 -1329 3.168
ZnH2 Zinc hydride 3 Πu 633 462 -171 1.370
GeH2 germylene 2 A1 916 1932 1016 0.474
C4H6O2 2,3-Butanedione 9 Ag 614 507 -107 1.211
C4H6O2 2,3-Butanedione 21 Bg 240 113 -127 2.121
C2H3NO3 Oxamic acid 3 A' 2600 3481 881 0.747
C2H3NO3 Oxamic acid 15 A' 328 260 -68 1.261
C2H3NO3 Oxamic acid 17 A" 815 640 -175 1.274
C5H8 1,4-Pentadiene 17 A 102 81 -21 1.253
C6H10 1,5-Hexadiene 29 Bg 264 157 -107 1.678
COBr2 Carbonic dibromide 4 B1 757 488 -269 1.553
C2F2 difluoroacetylene 4 Πg 270 195 -75 1.384
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.230
C5H8 1,3-Pentadiene, (E)- 32 A" 129 185 56 0.696
C3H4O2 β–Propiolactone 21 A" 113 164 51 0.688
CH3OH Methyl alcohol 12 A" 200 319 119 0.628
CH3NH2 methyl amine 14 A" 1195 938 -257 1.274
C6H4O2 parabenzoquinone 4 Ag 1147 1701 554 0.674
C6H4O2 parabenzoquinone 13 B1u 944 1678 734 0.563
C6H4O2 parabenzoquinone 17 B2g 241 919 678 0.262
C3H6O 2-Propen-1-ol 24 A 188 105 -83 1.796
C5H12 Pentane 23 A2 131 101 -30 1.295
C3H3 Propargyl radical 7 B1 490 396 -94 1.236
BF3+ boron trifluoride cation 3 E' 1662 568 -1094 2.926
O3 Ozone 3 B2 1042 867 -175 1.201
N2O3 Dinitrogen trioxide 9 A" 63 133 70 0.474
SiH- silicon monohydride anion 1 Σ 2175 1766 -409 1.231
C2H3N3 1H-1,2,4-Triazole 18 A" 640 506 -134 1.264
C2H3NO3 Oxamic acid 20 A" 315 248 -67 1.269
C5H8 1,4-Pentadiene 31 B 721 577 -144 1.249
C5H8 1,4-Pentadiene 33 B 331 90 -241 3.666
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.274
C4N2 2-Butynedinitrile 3 Σg 692 569 -123 1.217
CH3 Methyl radical 2 A2" 606 395 -212 1.536
CH2OH Hydroxymethyl radical 9 A 234 421 187 0.556
C6H6 Benzene 8 B2g 703 539 -164 1.303
CBr2F2 Methane, dibromodifluoro- 3 A1 140 319 179 0.439
C6H5CN phenyl cyanide 19 B1 688 559 -129 1.231
C6H4O2 parabenzoquinone 6 Ag 443 1120 677 0.396
C6H4O2 parabenzoquinone 19 B2u 1592 3086 1494 0.516