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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 MP2/6-31G*
Calculated values were scaled by 0.943.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.698
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3COCH3 Acetone 12 A2 77 57 -20 1.348
CH3COCH3 Acetone 12 A2 77 56 -21 1.367
CH3COCH3 Acetone 12 A2 77 57 -20 1.348
CH3COCH3 Acetone 12 A2 77 56 -21 1.367
C2H6O2S Dimethyl sulfone 20 B1 262 217 -45 1.207
C2H6O2S Dimethyl sulfone 20 B1 262 217 -45 1.207
C6H6 Benzene 8 B2g 703 477 -226 1.473
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 313 99 0.685
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 315 101 0.679
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 313 99 0.685
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 315 101 0.679
C2H2 Acetylene 4 Πg 612 353 -259 1.732
HCN+ hydrogen cyanide cation 1 Σ 3050 3745 695 0.814
HCN+ hydrogen cyanide cation 2 Σ 1800 2789 989 0.645
C2H5Br Ethyl bromide 8 A' 1061 1473 412 0.720
C2H5Br Ethyl bromide 8 A' 1061 1473 412 0.720
C2H5Br Ethyl bromide 9 A' 964 1462 498 0.659
C2H5Br Ethyl bromide 9 A' 964 1462 498 0.659
C2H5Br Ethyl bromide 10 A' 583 1462 879 0.399
C2H5Br Ethyl bromide 10 A' 583 1462 879 0.399
C2H5Br Ethyl bromide 11 A' 290 1387 1097 0.209
C2H5Br Ethyl bromide 11 A' 290 1387 1097 0.209
C2H5Br Ethyl bromide 4 A' 1451 2988 1537 0.486
C2H5Br Ethyl bromide 4 A' 1451 2988 1537 0.486
C2H5Br Ethyl bromide 5 A' 1451 2934 1483 0.495
C2H5Br Ethyl bromide 5 A' 1451 2934 1483 0.495
C2H5Br Ethyl bromide 6 A' 1386 2934 1548 0.472
C2H5Br Ethyl bromide 6 A' 1386 2934 1548 0.472
CH3CCH propyne 9 E 633 486 -147 1.302
CH3CCH propyne 9 E 633 486 -147 1.303
CH3CCH propyne 9 E 633 486 -147 1.302
CH3CCH propyne 9 E 633 486 -147 1.303
CH3CCH propyne 10 E 328 217 -111 1.511
CH3CCH propyne 10 E 328 217 -111 1.511
CH3CCH propyne 10 E 328 217 -111 1.511
CH3CCH propyne 10 E 328 217 -111 1.511
CHONH2 formamide 12 A" 289 -129 -418 -2.239
CHONH2 formamide 12 A" 289 -129 -418 -2.237
CHONH2 formamide 12 A" 289 -129 -418 -2.239
CHONH2 formamide 12 A" 289 -129 -418 -2.237
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.225
CH3COCl Acetyl Chloride 15 A" 166 135 -31 1.227
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.225
CH3COCl Acetyl Chloride 15 A" 166 135 -31 1.227
CBr2F2 Methane, dibromodifluoro- 3 A1 140 320 180 0.437
C3F8 perfluoropropane 13 A2 276 211 -65 1.307
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.209
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.327
CH3COCH2CH3 2-Butanone 33 A" 87 35 -52 2.494
CH3COOCH3 methyl acetate 27 A" 110 67 -43 1.641
CH3COOCH3 methyl acetate 27 A" 110 68 -42 1.624
CH3COOCH3 methyl acetate 27 A" 110 67 -43 1.641
CH3COOCH3 methyl acetate 27 A" 110 68 -42 1.624
C9H8 Indene 40 A" 690 503 -187 1.371
C9H8 Indene 41 A" 549 430 -119 1.276
C6H5NO2 Nitrobenzene 22 B1 675 470 -205 1.436
C6H5CN phenyl cyanide 19 B1 688 519 -169 1.325
C6H5CN phenyl cyanide 19 B1 688 519 -169 1.326
C6H5CN phenyl cyanide 19 B1 688 519 -169 1.325
C6H5CN phenyl cyanide 19 B1 688 519 -169 1.326
C6H5CHO benzaldehyde 32 A" 688 478 -210 1.440
C6H5CHO benzaldehyde 32 A" 688 478 -210 1.440
C6H5CHO benzaldehyde 32 A" 688 478 -210 1.440
C6H5CHO benzaldehyde 32 A" 688 478 -210 1.440
C6H4O2 parabenzoquinone 16 B2g 794 638 -156 1.245
C6H4O2 parabenzoquinone 17 B2g 241 169 -72 1.425
C6H4O2 parabenzoquinone 30 B3u 109 85 -24 1.282
CHCCH2CH3 1-Butyne 13 A' 634 524 -110 1.209
CHCCH2CH3 1-Butyne 22 A" 630 494 -136 1.276
C3H6O 2-Propen-1-ol 24 A 188 108 -81 1.748
C6H5Cl chlorobenzene 18 B1 685 462 -222 1.481
C3H2N2 Malononitrile 6 A1 167 133 -34 1.260
C3H2N2 Malononitrile 6 A1 167 132 -35 1.261
C3H2N2 Malononitrile 6 A1 167 133 -34 1.260
C3H2N2 Malononitrile 6 A1 167 132 -35 1.261
C4H4N2 Succinonitrile 17 Bg 387 320 -67 1.211
C5H8 Cyclopentene 18 A' 254 173 -81 1.471
C4H4N2 Pyridazine 13 A2 421 338 -83 1.247
CH2NN diazomethane 6 B1 406 -127 -533 -3.204
CH2NN diazomethane 6 B1 406 -104 -510 -3.911
CH2NN diazomethane 6 B1 406 -127 -533 -3.204
CH2NN diazomethane 6 B1 406 -104 -510 -3.911
NH2CN cyanamide 5 A' 408 654 246 0.624
C6H5F Fluorobenzene 18 B1 685 491 -194 1.394
C4H2 Diacetylene 8 Πu 630 425 -205 1.481
C4H2 Diacetylene 7 Πg 482 227 -255 2.127
C4H6O2 2,3-Butanedione 21 Bg 240 120 -120 2.008
C4H6O2 2,3-Butanedione 9 Ag 614 506 -108 1.214
C3H6O Oxetane 12 A2 986 819 -167 1.204
C3H6O Oxetane 18 B1 90 -86 -176 -1.039
C3H6O Oxetane 23 B2 1228 1009 -219 1.217
C2H3NO3 Oxamic acid 3 A' 2600 3423 823 0.760
C2H3NO3 Oxamic acid 15 A' 328 260 -68 1.262
C2H3NO3 Oxamic acid 16 A" 984 759 -225 1.297
C2H3NO3 Oxamic acid 17 A" 815 655 -160 1.244
C2H3NO3 Oxamic acid 18 A" 745 606 -139 1.229
C2H3NO3 Oxamic acid 20 A" 315 257 -58 1.224
C2H3NO3 Oxamic acid 21 A" 162 52 -110 3.121
CH3CCCH3 2-Butyne 16 E" 371 158 -213 2.348
C3O2 Carbon suboxide 7 Πu 61 100 39 0.608
C6H4F2 1,4-difluorobenzene 16 B2g 692 478 -214 1.447
C5H8 1,4-Pentadiene 16 A 137 290 153 0.472
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.235
C6H10 1,5-Hexadiene 29 Bg 264 163 -101 1.617
C6H10 1,5-Hexadiene 14 Ag 351 263 -88 1.336
COBr2 Carbonic dibromide 4 B1 757 489 -268 1.547
COBr2 Carbonic dibromide 6 B2 512 324 -188 1.583
CH3SSCH3 Disulfide, dimethyl 13 A 117 94 -23 1.248
C6H8 1,4-Cyclohexadiene 19 B1u 108 80 -28 1.346
CO+ carbon monoxide cation 1 Σ 2214 2722 508 0.813
CO+ carbon monoxide cation 1 Σ 2214 2722 508 0.813
CO+ carbon monoxide cation 1 Σ 2214 2722 508 0.813
CO+ carbon monoxide cation 1 Σ 2214 2722 508 0.813
CH2D2 methane-d2 6 B1 3013 2269 -744 1.328
CH2D2 methane-d2 8 B2 2234 3063 829 0.729
C2F2 difluoroacetylene 4 Πg 270 174 -96 1.555
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.221
C4N2 2-Butynedinitrile 3 Σg 692 573 -119 1.208
GeO2 Germanium dioxide 3 Πu 196 154 -41 1.269
NaOH sodium hydroxide 3 Π 300 116 -184 2.596
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.669
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.387
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 112 -59 1.527
CH3OCH2CN Methoxyacetonitrile 15 A' 243 165 -78 1.472
CH3OCH2CN Methoxyacetonitrile 24 A" 113 83 -30 1.354
C2H5 Ethyl radical 9 A' 528 437 -91 1.207
CN Cyano radical 1 Σ 2069 2699 631 0.766
CN Cyano radical 1 Σ 2069 2699 631 0.766
CN Cyano radical 1 Σ 2069 2699 631 0.766
CN Cyano radical 1 Σ 2069 2699 631 0.766
C2H Ethynyl radical 2 Σ 1841 2342 502 0.786
C2H Ethynyl radical 3 Π 372 772 400 0.481
CH3 Methyl radical 2 A2" 606 376 -231 1.615
CH3 Methyl radical 2 A2" 606 376 -231 1.615
CH3 Methyl radical 2 A2" 606 376 -231 1.615
CH3 Methyl radical 2 A2" 606 376 -231 1.615
CH3OO methylperoxy radical 12 A" 170 129 -41 1.319
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 89 -269 4.006
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 123 -141 2.141
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 864 -272 1.315
CH2OH Hydroxymethyl radical 9 A 234 436 202 0.537
CH2OH Hydroxymethyl radical 8 A 482 742 260 0.650
CH2CHO Vinyloxy radical 10 A" 703 1016 313 0.692
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.371
C4H6 Methylenecyclopropane 17 B1 360 264 -96 1.365
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.371
C4H6 Methylenecyclopropane 17 B1 360 264 -96 1.365
C2Cl2+ dichloroacetylene cation 5 Πu 233 168 -65 1.385
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.204
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.204
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.204
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.204
BF3+ boron trifluoride cation 3 E' 1662 2153 492 0.772
O2+ diatomic oxygen cation 1 Σg 1906 1266 -640 1.506
O2+ diatomic oxygen cation 1 Σg 1906 1266 -640 1.506
O2+ diatomic oxygen cation 1 Σg 1906 1266 -640 1.506
O2+ diatomic oxygen cation 1 Σg 1906 1266 -640 1.506
MgF2 Magnesium fluoride 3 Πu 165 135 -30 1.224
FOOF Perfluoroperoxide 1 A 1210 951 -259 1.272
SF4 Sulfur tetrafluoride 4 A1 228 187 -41 1.217
SF4 Sulfur tetrafluoride 4 A1 228 188 -40 1.214
SF4 Sulfur tetrafluoride 4 A1 228 187 -41 1.217
SF4 Sulfur tetrafluoride 4 A1 228 188 -40 1.214
AsH3+ Arsine cation 2 A1 452 665 213 0.679
BrF5 bromine pentafluoride 6 B2 281 214 -67 1.316
BrF5 bromine pentafluoride 6 B2 281 214 -67 1.315
BrF5 bromine pentafluoride 6 B2 281 214 -67 1.316
BrF5 bromine pentafluoride 6 B2 281 214 -67 1.315
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.327
O3 Ozone 3 B2 1042 2244 1201 0.464
O3 Ozone 3 B2 1042 2244 1202 0.464
O3 Ozone 3 B2 1042 2244 1201 0.464
O3 Ozone 3 B2 1042 2244 1202 0.464
NO Nitric oxide 1 Σ 1904 3691 1786 0.516
NO Nitric oxide 1 Σ 1904 3690 1785 0.516
NO Nitric oxide 1 Σ 1904 3691 1786 0.516
NO Nitric oxide 1 Σ 1904 3690 1785 0.516
NO2 Nitrogen dioxide 3 B2 1618 2142 524 0.755
NO2 Nitrogen dioxide 3 B2 1618 2141 523 0.756
NO2 Nitrogen dioxide 3 B2 1618 2142 524 0.755
NO2 Nitrogen dioxide 3 B2 1618 2141 523 0.756
N2O4 Dinitrogen tetroxide 9 B2u 265 182 -83 1.457
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.213
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.213
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.213
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.213
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.384
N2O3 Dinitrogen trioxide 9 A" 63 165 102 0.382
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.384
N2O3 Dinitrogen trioxide 9 A" 63 165 102 0.382
NS+ nitrogen sulfide cation 1 Σ 1415 1162 -253 1.218
Li2O dilithium oxide 3 Πu 112 62 -50 1.812
FO Oxygen monofluoride 1 Σ 1053 2348 1295 0.449
FO Oxygen monofluoride 1 Σ 1053 2347 1294 0.449
FO Oxygen monofluoride 1 Σ 1053 2348 1295 0.449
FO Oxygen monofluoride 1 Σ 1053 2347 1294 0.449
C3 carbon trimer 3 Πu 63 166 102 0.383
C3 carbon trimer 3 Πu 63 166 102 0.383
C3 carbon trimer 3 Πu 63 166 102 0.383
C3 carbon trimer 3 Πu 63 166 102 0.383
C5H5- cylopentadienyl anion 8 E1" 625 504 -121 1.239
C5H5- cylopentadienyl anion 14 E2" 600 480 -120 1.249
CaOH Calcium monohydroxide 2 Σ 353 603 250 0.585
CaOH Calcium monohydroxide 3 Π 609 377 -232 1.617
Cu2 Copper dimer 1 Σg 265 382 118 0.692
PS phosphorus sulfide 1 Σ 739 1180 441 0.626
ClNO2 Nitryl chloride 3 A1 364 302 -62 1.207
ClNO2 Nitryl chloride 3 A1 364 302 -62 1.207
ClNO2 Nitryl chloride 3 A1 364 302 -62 1.207
ClNO2 Nitryl chloride 3 A1 364 302 -62 1.207
SiH- silicon monohydride anion 1 Σ 2175 1793 -382 1.213
SiH- silicon monohydride anion 1 Σ 2175 1793 -382 1.213
SiH- silicon monohydride anion 1 Σ 2175 1793 -382 1.213
SiH- silicon monohydride anion 1 Σ 2175 1793 -382 1.213
SF5Cl sulfur chloropentafluoride 5 B1 625 444 -181 1.407
SF5Cl sulfur chloropentafluoride 7 B2 505 303 -202 1.669
SF5Cl sulfur chloropentafluoride 11 E 397 239 -158 1.663
ZnH2 Zinc hydride 3 Πu 633 494 -139 1.281
PO Phosphorus monoxide 1 Σ 1233 3868 2635 0.319
PO Phosphorus monoxide 1 Σ 1233 3869 2636 0.319
PO Phosphorus monoxide 1 Σ 1233 3868 2635 0.319
PO Phosphorus monoxide 1 Σ 1233 3869 2636 0.319
AlO Aluminum monoxide 1 Σ 979 724 -255 1.352
SCN thiocyanato radical 1 Σ 1942 2414 472 0.805
PN Phosphorus mononitride 1 Σ 1337 1086 -251 1.231
PN Phosphorus mononitride 1 Σ 1337 1085 -252 1.232
PN Phosphorus mononitride 1 Σ 1337 1086 -251 1.231
PN Phosphorus mononitride 1 Σ 1337 1085 -252 1.232
NCO isocyanato radical 1 Σ 1921 2366 444 0.812
NCO isocyanato radical 1 Σ 1921 2366 445 0.812
NCO isocyanato radical 1 Σ 1921 2366 444 0.812
NCO isocyanato radical 1 Σ 1921 2366 445 0.812
GeH2 germylene 1 A1 1856 916 -940 2.027
GeH2 germylene 2 A1 916 1785 869 0.513
H2POH Phosphinous acid 9 A" 375 258 -117 1.455
AsN Arsenic mononitride 1 Σ 1069 824 -244 1.297
Mg2 Magnesium diatomic 1 Σg 51 320 269 0.160
Mg2 Magnesium diatomic 1 Σg 51 320 269 0.160
Mg2 Magnesium diatomic 1 Σg 51 320 269 0.160
Mg2 Magnesium diatomic 1 Σg 51 320 269 0.160
ZnCH3 Zinc monomethyl 6 E 315 605 290 0.520
ClOO chloroperoxy radical 3 A' 201 468 267 0.430
ClOO chloroperoxy radical 2 A' 414 1030 616 0.402
ONONO Nitrosyl nitrite 9 B2 380 259 -121 1.468