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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=FULL/6-31G*
Calculated values were scaled by 0.9422.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.697
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3COCH3 Acetone 12 A2 77 57 -20 1.348
CH3COCH3 Acetone 12 A2 77 57 -20 1.354
CH3COCH3 Acetone 12 A2 77 57 -20 1.348
CH3COCH3 Acetone 12 A2 77 57 -20 1.354
C2H6O2S Dimethyl sulfone 20 B1 262 218 -44 1.200
C2H6O2S Dimethyl sulfone 20 B1 262 218 -44 1.200
C6H6 Benzene 8 B2g 703 498 -205 1.411
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 313 99 0.684
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 316 102 0.678
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 313 99 0.684
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 316 102 0.678
C2H2 Acetylene 4 Πg 612 374 -238 1.637
HCN+ hydrogen cyanide cation 1 Σ 3050 3726 676 0.819
HCN+ hydrogen cyanide cation 2 Σ 1800 2784 984 0.647
CH3CCH propyne 9 E 633 496 -137 1.275
CH3CCH propyne 9 E 633 494 -139 1.281
CH3CCH propyne 9 E 633 496 -137 1.275
CH3CCH propyne 9 E 633 494 -139 1.281
CH3CCH propyne 10 E 328 238 -90 1.376
CH3CCH propyne 10 E 328 237 -91 1.382
CH3CCH propyne 10 E 328 238 -90 1.376
CH3CCH propyne 10 E 328 237 -91 1.382
CHONH2 formamide 12 A" 289 -112 -401 -2.569
CHONH2 formamide 12 A" 289 -110 -399 -2.616
CHONH2 formamide 12 A" 289 -112 -401 -2.569
CHONH2 formamide 12 A" 289 -110 -399 -2.616
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.221
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.224
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.221
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.224
CBr2F2 Methane, dibromodifluoro- 3 A1 140 322 182 0.435
C3F8 perfluoropropane 13 A2 276 212 -64 1.305
CH3COCH2CH3 2-Butanone 33 A" 87 35 -52 2.459
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.208
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 56 -19 1.345
CH3COOCH3 methyl acetate 27 A" 110 68 -42 1.614
CH3COOCH3 methyl acetate 27 A" 110 68 -42 1.614
CH3COOCH3 methyl acetate 27 A" 110 68 -42 1.614
CH3COOCH3 methyl acetate 27 A" 110 68 -42 1.614
C9H8 Indene 40 A" 690 512 -178 1.348
C9H8 Indene 41 A" 549 453 -96 1.212
C6H5NO2 Nitrobenzene 22 B1 675 492 -183 1.371
C6H5CN phenyl cyanide 19 B1 688 535 -153 1.285
C6H5CN phenyl cyanide 19 B1 688 535 -153 1.286
C6H5CN phenyl cyanide 19 B1 688 535 -153 1.285
C6H5CN phenyl cyanide 19 B1 688 535 -153 1.286
C6H5CHO benzaldehyde 32 A" 688 499 -189 1.379
C6H5CHO benzaldehyde 32 A" 688 499 -189 1.379
C6H5CHO benzaldehyde 32 A" 688 499 -189 1.379
C6H5CHO benzaldehyde 32 A" 688 499 -189 1.379
C6H4O2 parabenzoquinone 16 B2g 794 657 -137 1.209
C6H4O2 parabenzoquinone 17 B2g 241 179 -62 1.350
C6H4O2 parabenzoquinone 30 B3u 109 86 -23 1.265
CHCCH2CH3 1-Butyne 13 A' 634 528 -106 1.200
CHCCH2CH3 1-Butyne 22 A" 630 502 -128 1.254
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.752
C6H5Cl chlorobenzene 18 B1 685 489 -196 1.401
C5H12 Pentane 23 A2 131 105 -26 1.244
C3H2N2 Malononitrile 6 A1 167 134 -33 1.242
C3H2N2 Malononitrile 6 A1 167 134 -33 1.242
C3H2N2 Malononitrile 6 A1 167 134 -33 1.242
C3H2N2 Malononitrile 6 A1 167 134 -33 1.242
C5H8 Cyclopentene 18 A' 254 174 -80 1.460
C2H3N3 1H-1,2,4-Triazole 14 A" 990 821 -169 1.206
C4H4N2 Pyridazine 13 A2 421 341 -80 1.235
CH2NN diazomethane 6 B1 406 -58 -464 -6.966
NH2CN cyanamide 5 A' 408 649 241 0.629
C4H6O2 2,3-Butanedione 9 Ag 614 507 -107 1.212
C4H6O2 2,3-Butanedione 21 Bg 240 121 -119 1.990
C4H2 Diacetylene 7 Πg 482 331 -151 1.455
C4H2 Diacetylene 8 Πu 630 441 -189 1.428
C6H5F Fluorobenzene 18 B1 685 511 -174 1.339
C2H3NO3 Oxamic acid 3 A' 2600 3421 821 0.760
C2H3NO3 Oxamic acid 15 A' 328 260 -68 1.260
C2H3NO3 Oxamic acid 16 A" 984 771 -213 1.277
C2H3NO3 Oxamic acid 17 A" 815 658 -157 1.239
C2H3NO3 Oxamic acid 18 A" 745 608 -137 1.225
C2H3NO3 Oxamic acid 21 A" 162 58 -104 2.780
C3O2 Carbon suboxide 7 Πu 61 113 52 0.542
C6H4F2 1,4-difluorobenzene 16 B2g 692 512 -180 1.352
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.235
C6H10 1,5-Hexadiene 14 Ag 351 263 -88 1.333
C6H10 1,5-Hexadiene 29 Bg 264 165 -99 1.604
COBr2 Carbonic dibromide 4 B1 757 495 -262 1.529
COBr2 Carbonic dibromide 6 B2 512 326 -186 1.572
C6H8 1,4-Cyclohexadiene 19 B1u 108 83 -25 1.308
CH3SSCH3 Disulfide, dimethyl 13 A 117 94 -23 1.240
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 2268 -745 1.328
CH2D2 methane-d2 8 B2 2234 3062 828 0.730
C2F2 difluoroacetylene 4 Πg 270 224 -46 1.204
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.219
C4N2 2-Butynedinitrile 3 Σg 692 573 -119 1.207
NaOH sodium hydroxide 3 Π 300 161 -139 1.869
GeO2 Germanium dioxide 3 Πu 196 150 -46 1.305
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.380
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 330 -126 1.380
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.380
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 330 -126 1.380
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 114 -57 1.505
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 114 -57 1.504
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 114 -57 1.505
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 114 -57 1.504
C2H5 Ethyl radical 9 A' 528 438 -91 1.207
CN Cyano radical 1 Σ 2069 2703 634 0.765
CN Cyano radical 1 Σ 2069 2703 634 0.765
CN Cyano radical 1 Σ 2069 2703 634 0.765
CN Cyano radical 1 Σ 2069 2703 634 0.765
C2H Ethynyl radical 2 Σ 1841 2347 506 0.784
C2H Ethynyl radical 3 Π 372 777 406 0.478
CH3OO methylperoxy radical 12 A" 170 130 -40 1.305
CH3 Methyl radical 2 A2" 606 378 -228 1.604
CH3 Methyl radical 2 A2" 606 378 -228 1.604
CH3 Methyl radical 2 A2" 606 378 -228 1.604
CH3 Methyl radical 2 A2" 606 378 -228 1.604
CH2OH Hydroxymethyl radical 8 A 482 739 257 0.652
CH2OH Hydroxymethyl radical 9 A 234 435 201 0.537
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 864 -272 1.314
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 125 -139 2.107
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 90 -268 3.965
CH2CHO Vinyloxy radical 10 A" 703 1017 314 0.691
C4H6 Methylenecyclopropane 17 B1 360 266 -94 1.352
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.346
C4H6 Methylenecyclopropane 17 B1 360 266 -94 1.352
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.346
C2Cl2 dichloroacetylene 4 Πg 333 136 -197 2.451
C2Cl2+ dichloroacetylene cation 5 Πu 233 172 -61 1.351
BF3+ boron trifluoride cation 3 E' 1662 2161 499 0.769
O2+ diatomic oxygen cation 1 Σg 1906 1271 -635 1.500
O2+ diatomic oxygen cation 1 Σg 1906 1271 -635 1.500
O2+ diatomic oxygen cation 1 Σg 1906 1271 -635 1.500
O2+ diatomic oxygen cation 1 Σg 1906 1271 -635 1.500
AsH3+ Arsine cation 2 A1 452 662 210 0.683
FOOF Perfluoroperoxide 1 A 1210 953 -257 1.270
D2O Deuterium oxide 1 A1 2671 3558 887 0.751
D2O Deuterium oxide 1 A1 2671 3558 887 0.751
D2O Deuterium oxide 2 A1 1178 1636 458 0.720
D2O Deuterium oxide 2 A1 1178 1636 458 0.720
D2O Deuterium oxide 3 B2 2788 3691 903 0.755
D2O Deuterium oxide 3 B2 2788 3691 903 0.755
BrF5 bromine pentafluoride 6 B2 281 216 -65 1.299
BrF5 bromine pentafluoride 6 B2 281 216 -65 1.299
BrF5 bromine pentafluoride 6 B2 281 216 -65 1.299
BrF5 bromine pentafluoride 6 B2 281 216 -65 1.299
O3 Ozone 3 B2 1042 2236 1194 0.466
O3 Ozone 3 B2 1042 2236 1194 0.466
O3 Ozone 3 B2 1042 2236 1194 0.466
O3 Ozone 3 B2 1042 2236 1194 0.466
NO Nitric oxide 1 Σ 1904 3670 1766 0.519
NO Nitric oxide 1 Σ 1904 3668 1764 0.519
NO Nitric oxide 1 Σ 1904 3670 1766 0.519
NO Nitric oxide 1 Σ 1904 3668 1764 0.519
NO2 Nitrogen dioxide 3 B2 1618 2158 540 0.750
NO2 Nitrogen dioxide 3 B2 1618 2157 539 0.750
PCl5 Phosphorus pentachloride 2 A1' 370 278 -92 1.332
NO2 Nitrogen dioxide 3 B2 1618 2158 540 0.750
NO2 Nitrogen dioxide 3 B2 1618 2157 539 0.750
N2O4 Dinitrogen tetroxide 9 B2u 265 183 -82 1.451
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.211
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.211
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.211
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.211
N2O3 Dinitrogen trioxide 9 A" 63 166 103 0.380
N2O3 Dinitrogen trioxide 9 A" 63 166 103 0.380
N2O3 Dinitrogen trioxide 9 A" 63 166 103 0.380
N2O3 Dinitrogen trioxide 9 A" 63 166 103 0.380
NS+ nitrogen sulfide cation 1 Σ 1415 1166 -249 1.213
Li2O dilithium oxide 3 Πu 112 58 -53 1.909
FO Oxygen monofluoride 1 Σ 1053 2350 1297 0.448
FO Oxygen monofluoride 1 Σ 1053 2350 1297 0.448
C3 carbon trimer 3 Πu 63 179 116 0.354
C3 carbon trimer 3 Πu 63 179 115 0.354
C3 carbon trimer 3 Πu 63 179 116 0.354
C3 carbon trimer 3 Πu 63 179 115 0.354
C5H5- cylopentadienyl anion 8 E1" 625 513 -112 1.219
C5H5- cylopentadienyl anion 14 E2" 600 492 -108 1.220
CaOH Calcium monohydroxide 2 Σ 353 603 250 0.585
CaOH Calcium monohydroxide 3 Π 609 377 -232 1.615
Cu2 Copper dimer 1 Σg 265 391 126 0.677
PS phosphorus sulfide 1 Σ 739 1202 463 0.615
ClNO2 Nitryl chloride 3 A1 364 301 -62 1.207
ClNO2 Nitryl chloride 3 A1 364 303 -61 1.201
ClNO2 Nitryl chloride 3 A1 364 301 -62 1.207
ClNO2 Nitryl chloride 3 A1 364 303 -61 1.201
Fe(CO)5 Iron pentacarbonyl 15 E' 74 60 -15 1.244
SiH- silicon monohydride anion 1 Σ 2175 1791 -384 1.214
SiH- silicon monohydride anion 1 Σ 2175 1791 -384 1.214
SiH- silicon monohydride anion 1 Σ 2175 1791 -384 1.214
SiH- silicon monohydride anion 1 Σ 2175 1791 -384 1.214
SF5Cl sulfur chloropentafluoride 5 B1 625 448 -177 1.395
SF5Cl sulfur chloropentafluoride 7 B2 505 305 -200 1.657
SF5Cl sulfur chloropentafluoride 11 E 397 241 -156 1.648
ZnH2 Zinc hydride 3 Πu 633 522 -111 1.212
PO Phosphorus monoxide 1 Σ 1233 3834 2600 0.322
PO Phosphorus monoxide 1 Σ 1233 3834 2601 0.322
PO Phosphorus monoxide 1 Σ 1233 3834 2600 0.322
PO Phosphorus monoxide 1 Σ 1233 3834 2601 0.322
AlO Aluminum monoxide 1 Σ 979 724 -255 1.353
SCN thiocyanato radical 1 Σ 1942 2408 466 0.807
ClOO chloroperoxy radical 2 A' 414 1031 617 0.401
ClOO chloroperoxy radical 3 A' 201 469 267 0.430
PN Phosphorus mononitride 1 Σ 1337 1090 -247 1.226
PN Phosphorus mononitride 1 Σ 1337 1089 -247 1.227
PN Phosphorus mononitride 1 Σ 1337 1090 -247 1.226
PN Phosphorus mononitride 1 Σ 1337 1089 -247 1.227
NCO isocyanato radical 1 Σ 1921 2364 443 0.813
NCO isocyanato radical 1 Σ 1921 2365 443 0.813
NCO isocyanato radical 1 Σ 1921 2364 443 0.813
NCO isocyanato radical 1 Σ 1921 2365 443 0.813
GeH2 germylene 1 A1 1856 913 -943 2.034
GeH2 germylene 2 A1 916 1786 870 0.513
H2POH Phosphinous acid 9 A" 375 257 -118 1.458
AsN Arsenic mononitride 1 Σ 1069 830 -238 1.287
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.308
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.308
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.308
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.308
ZnCH3 Zinc monomethyl 6 E 315 614 299 0.513
ONONO Nitrosyl nitrite 9 B2 380 259 -121 1.469