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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/6-31+G**
Calculated values were scaled by 0.9454.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 18 A" 93 69 -24 1.352
CH3OH Methyl alcohol 12 A" 200 302 102 0.663
CH3OH Methyl alcohol 12 A" 200 304 104 0.659
CH3OH Methyl alcohol 12 A" 200 302 102 0.663
CH3OH Methyl alcohol 12 A" 200 304 104 0.659
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.211
C6H6 Benzene 8 B2g 703 404 -299 1.739
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 307 93 0.696
C2H2 Acetylene 4 Πg 612 443 -169 1.381
CH3CCH propyne 10 E 328 251 -77 1.309
CH3COCl Acetyl Chloride 15 A" 166 121 -45 1.377
CBr2F2 Methane, dibromodifluoro- 3 A1 140 325 185 0.430
C3F8 perfluoropropane 13 A2 276 216 -60 1.279
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 519 -113 1.217
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.326
CH3COOCH3 methyl acetate 27 A" 110 45 -65 2.454
C9H8 Indene 40 A" 690 472 -218 1.461
C9H8 Indene 41 A" 549 432 -117 1.271
C6H5CHO benzaldehyde 32 A" 688 440 -248 1.563
C6H5CHO benzaldehyde 36 A" 111 92 -19 1.202
C6H4O2 parabenzoquinone 23 B3g 3044 953 -2091 3.194
C6H4O2 parabenzoquinone 24 B3g 1374 813 -561 1.689
C6H4O2 parabenzoquinone 25 B3g 1211 722 -489 1.676
CH2CHCHCH2 1,3-Butadiene 13 Au 162 129 -33 1.259
C3H6O 2-Propen-1-ol 24 A 188 105 -84 1.799
C6H5Cl chlorobenzene 18 B1 685 445 -239 1.537
C6H5Cl chlorobenzene 19 B1 467 386 -81 1.211
C5H12 Pentane 23 A2 131 97 -34 1.356
C3H2N2 Malononitrile 6 A1 167 136 -31 1.230
C4H5N Pyrrole 16 B1 475 378 -96 1.254
C4H4N2 Succinonitrile 17 Bg 387 313 -74 1.237
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 149 -44 1.293
C2Cl4 Tetrachloroethylene 4 Au 110 88 -22 1.244
C2Cl4 Tetrachloroethylene 7 B2g 512 296 -216 1.728
C5H8 Cyclopentene 18 A' 254 164 -90 1.550
C3H4N2 1H-Imidazole 21 A" 539 423 -116 1.273
C2H3N3 1H-1,2,4-Triazole 18 A" 640 481 -159 1.330
C2H4O3 trioxolane124 21 B 193 160 -33 1.204
C4H4N2 Pyridazine 12 A2 751 624 -127 1.204
C4H4N2 Pyridazine 13 A2 421 328 -93 1.282
NH2CN cyanamide 5 A' 408 629 221 0.649
NH2CN cyanamide 9 A" 435 351 -84 1.240
C4H6O2 2,3-Butanedione 9 Ag 614 505 -109 1.217
C4H6O2 2,3-Butanedione 16 Au 48 35 -13 1.391
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.229
C6H5F Fluorobenzene 18 B1 685 482 -203 1.421
C3O2 Carbon suboxide 7 Πu 61 119 58 0.511
C6H4F2 1,4-difluorobenzene 16 B2g 692 462 -230 1.499
C5H8 1,4-Pentadiene 16 A 137 284 147 0.483
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.223
C6H10 1,5-Hexadiene 14 Ag 351 258 -93 1.361
C6H10 1,5-Hexadiene 20 Au 649 534 -115 1.216
C6H10 1,5-Hexadiene 29 Bg 264 100 -164 2.647
COBr2 Carbonic dibromide 4 B1 757 503 -254 1.505
COBr2 Carbonic dibromide 6 B2 512 338 -174 1.515
CH3SSCH3 Disulfide, dimethyl 13 A 117 91 -26 1.285
C6H8 1,4-Cyclohexadiene 19 B1u 108 75 -33 1.443
C6H8 1,4-Cyclohexadiene 23 B2g 403 291 -112 1.386
CH2D2 methane-d2 6 B1 3013 2254 -759 1.337
CH2D2 methane-d2 8 B2 2234 3044 810 0.734
C2F2 difluoroacetylene 4 Πg 270 222 -48 1.218
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 139 -78 1.563
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.222
C4N2 2-Butynedinitrile 3 Σg 692 569 -123 1.217
C4N2 2-Butynedinitrile 6 Πg 504 291 -213 1.729
C4N2 2-Butynedinitrile 7 Πg 263 149 -114 1.766
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.678
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.678
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 320 -136 1.425
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 320 -136 1.425
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 93 -78 1.837
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 93 -78 1.832
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.678
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.678
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 320 -136 1.425
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 320 -136 1.425
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 93 -78 1.837
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 93 -78 1.832
C6H5O phenoxy radical 18 B1 635 517 -118 1.229
C6H5O phenoxy radical 19 B1 472 366 -106 1.290
CH3 Methyl radical 2 A2" 606 458 -148 1.324
CH3 Methyl radical 2 A2" 606 458 -148 1.324
CH3 Methyl radical 2 A2" 606 458 -148 1.324
CH3 Methyl radical 2 A2" 606 458 -148 1.324
CH2OH Hydroxymethyl radical 9 A 234 420 186 0.557
C3H3 Propargyl radical 7 B1 490 388 -102 1.262
C4H6 Methylenecyclopropane 17 B1 360 249 -111 1.448
C2Cl2 dichloroacetylene 4 Πg 333 60 -273 5.508
C2Cl2+ dichloroacetylene cation 4 Πg 318 223 -95 1.425
C2Cl2+ dichloroacetylene cation 5 Πu 233 164 -69 1.421
SiO2 silicon dioxide 3 Πu 273 211 -62 1.293
BF3+ boron trifluoride cation 3 E' 1662 578 -1083 2.874
BF3+ boron trifluoride cation 4 E' 411 -992 -1403 -0.414
FOOF Perfluoroperoxide 1 A 1210 980 -230 1.234
AsH3+ Arsine cation 2 A1 452 664 212 0.681
PCl5 Phosphorus pentachloride 2 A1' 370 272 -98 1.362
O3 Ozone 3 B2 1042 812 -230 1.283
N2O3 Dinitrogen trioxide 9 A" 63 120 57 0.525
Li2O dilithium oxide 3 Πu 112 53 -58 2.098
C3 carbon trimer 3 Πu 63 -109 -172 -0.584
CaOH Calcium monohydroxide 2 Σ 353 551 198 0.640
CaOH Calcium monohydroxide 3 Π 609 407 -202 1.498
C4 Carbon tetramer 4 Πg 323 190 -133 1.704
SiH- silicon monohydride anion 1 Σ 2175 1794 -381 1.213
SiH- silicon monohydride anion 1 Σ 2175 1794 -381 1.212
SiH- silicon monohydride anion 1 Σ 2175 1794 -381 1.213
SiH- silicon monohydride anion 1 Σ 2175 1794 -381 1.212
SF5Cl sulfur chloropentafluoride 5 B1 625 446 -179 1.401
SF5Cl sulfur chloropentafluoride 7 B2 505 306 -199 1.652
SF5Cl sulfur chloropentafluoride 11 E 397 243 -154 1.635
Cl3- trichloride anion 2 Σu 327 194 -133 1.685
GeH2 germylene 1 A1 1856 919 -937 2.020
GeH2 germylene 2 A1 916 1936 1020 0.473
H2OH2O water dimer 8 A' 103 157 54 0.657
H2OH2O water dimer 11 A" 108 161 53 0.669
H2OH2O water dimer 12 A" 88 134 46 0.655
F3- trifluoride anion 2 Σu 550 306 -244 1.799
H2POH Phosphinous acid 9 A" 375 260 -115 1.444
Mg2 Magnesium diatomic 1 Σg 51 15 -37 3.516
Mg2 Magnesium diatomic 1 Σg 51 15 -37 3.516
Mg2 Magnesium diatomic 1 Σg 51 15 -37 3.516
Mg2 Magnesium diatomic 1 Σg 51 15 -37 3.516
Al2 Aluminum diatomic 1 Σg 286 432 146 0.661
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.530