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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
C2H2 Acetylene 4 Πg 612 443 -169 1.381
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.326
CH3COOCH3 methyl acetate 27 A" 110 45 -65 2.454
C6H5CHO benzaldehyde 32 A" 688 440 -248 1.563
C6H4O2 parabenzoquinone 23 B3g 3044 953 -2091 3.194
C3H6O 2-Propen-1-ol 21 A 554 423 -131 1.309
C6H5Cl chlorobenzene 18 B1 685 445 -239 1.537
C3H2N2 Malononitrile 6 A1 167 136 -31 1.230
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 149 -44 1.293
C5H8 Cyclopentene 18 A' 254 164 -90 1.550
C2H4O3 trioxolane124 21 B 193 160 -33 1.204
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
C6H10 1,5-Hexadiene 14 Ag 351 258 -93 1.361
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 139 -78 1.563
C4N2 2-Butynedinitrile 6 Πg 504 291 -213 1.729
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 93 -78 1.837
C2Cl2 dichloroacetylene 4 Πg 333 60 -273 5.508
C2Cl2+ dichloroacetylene cation 4 Πg 318 223 -95 1.425
AsH3+ Arsine cation 2 A1 452 664 212 0.681
Li2O dilithium oxide 3 Πu 112 53 -58 2.098
CaOH Calcium monohydroxide 3 Π 609 407 -202 1.498
NH2CN cyanamide 5 A' 408 629 221 0.649
C6H10 1,5-Hexadiene 20 Au 649 534 -115 1.216
COBr2 Carbonic dibromide 6 B2 512 338 -174 1.515
C6H10 2-Hexyne 38 A" 392 256 -136 1.534
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)- 31 A" 456 320 -136 1.425
C5H8 1,3-Pentadiene, (E)- 31 A" 361 221 -140 1.633
C6H5O phenoxy radical 19 B1 472 366 -106 1.290
C4H6 Methylenecyclopropane 17 B1 360 249 -111 1.448
CaOH Calcium monohydroxide 2 Σ 353 551 198 0.640
C4 Carbon tetramer 4 Πg 323 190 -133 1.704
GeH2 germylene 1 A1 1856 919 -937 2.020
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
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.211
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 307 93 0.696
CH3COCl Acetyl Chloride 15 A" 166 121 -45 1.377
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 519 -113 1.217
C6H5CHO benzaldehyde 36 A" 111 92 -19 1.202
C6H4O2 parabenzoquinone 25 B3g 1211 722 -489 1.676
CH2CHCHCH2 1,3-Butadiene 13 Au 162 129 -33 1.259
C4H8O Furan, tetrahydro- 33 B 137 53 -84 2.565
C2Cl4 Tetrachloroethylene 4 Au 110 88 -22 1.244
C3H3NO Isoxazole 14 A" 1033 838 -195 1.232
C4H4N2 Pyridazine 13 A2 421 328 -93 1.282
CH3OH Methyl alcohol 12 A" 200 302 102 0.663
CH3NH2 methyl amine 14 A" 1195 934 -261 1.279
C6H4O2 parabenzoquinone 24 B3g 1374 813 -561 1.689
C3H6O 2-Propen-1-ol 24 A 188 105 -84 1.799
C5H12 Pentane 23 A2 131 97 -34 1.356
C4H4N2 Succinonitrile 17 Bg 387 313 -74 1.237
C3H4N2 1H-Imidazole 21 A" 539 423 -116 1.273
C4H4N2 Pyridazine 12 A2 751 624 -127 1.204
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
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.223
C6H10 1,5-Hexadiene 29 Bg 264 100 -164 2.647
COBr2 Carbonic dibromide 4 B1 757 503 -254 1.505
C2F2 difluoroacetylene 4 Πg 270 222 -48 1.218
C6H10 2-Hexyne 25 A' 115 91 -24 1.270
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.222
C2Cl2+ dichloroacetylene cation 5 Πu 233 164 -69 1.421
SiO2 silicon dioxide 3 Πu 273 211 -62 1.293
BF3+ boron trifluoride cation 4 E' 411 -992 -1403 -0.414
PCl5 Phosphorus pentachloride 2 A1' 370 272 -98 1.362
GeH2 germylene 2 A1 916 1936 1020 0.473
C5H8 1,4-Pentadiene 31 B 721 575 -146 1.253
C5H8 1,4-Pentadiene 33 B 331 91 -240 3.631
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
C4N2 2-Butynedinitrile 3 Σg 692 569 -123 1.217
C6H5O phenoxy radical 18 B1 635 517 -118 1.229
CH3 Methyl radical 2 A2" 606 458 -148 1.324
C3H3 Propargyl radical 7 B1 490 388 -102 1.262
BF3+ boron trifluoride cation 3 E' 1662 578 -1083 2.874
O3 Ozone 3 B2 1042 812 -230 1.283
N2O3 Dinitrogen trioxide 9 A" 63 120 57 0.525
SiH- silicon monohydride anion 1 Σ 2175 1794 -381 1.213
C6H6 Benzene 8 B2g 703 404 -299 1.739
CH3CCH propyne 10 E 328 251 -77 1.309
CBr2F2 Methane, dibromodifluoro- 3 A1 140 325 185 0.430
C6H5Cl chlorobenzene 19 B1 467 386 -81 1.211
C4H5N Pyrrole 16 B1 475 378 -96 1.254
C2Cl4 Tetrachloroethylene 7 B2g 512 296 -216 1.728
C2H3N3 1H-1,2,4-Triazole 18 A" 640 481 -159 1.330
NH2CN cyanamide 9 A" 435 351 -84 1.240