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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 0.9365.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 11 A' 657 546 -111 1.203
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
CH3OH Methyl alcohol 12 A" 200 326 126 0.614
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
CH3OH Methyl alcohol 12 A" 200 326 126 0.614
CH3COCH3 Acetone 12 A2 77 53 -24 1.455
C2H6O2S Dimethyl sulfone 20 B1 262 217 -45 1.207
C6H6 Benzene 8 B2g 703 468 -235 1.503
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 312 98 0.685
CH3CCH propyne 9 E 633 517 -116 1.225
CH3CCH propyne 10 E 328 255 -73 1.285
HCN+ hydrogen cyanide cation 1 Σ 3050 3727 678 0.818
HCN+ hydrogen cyanide cation 2 Σ 1800 2775 975 0.649
C2H2 Acetylene 4 Πg 612 416 -196 1.473
CH3COCl Acetyl Chloride 15 A" 166 135 -31 1.226
CBr2F2 Methane, dibromodifluoro- 3 A1 140 318 178 0.440
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 517 -115 1.222
C3F8 perfluoropropane 13 A2 276 210 -66 1.316
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.306
CH3COCH2CH3 2-Butanone 33 A" 87 27 -60 3.164
CH3COOCH3 methyl acetate 27 A" 110 62 -48 1.767
C9H8 Indene 40 A" 690 496 -194 1.391
C9H8 Indene 41 A" 549 418 -131 1.314
C6H5CN phenyl cyanide 19 B1 688 511 -177 1.346
C6H5CHO benzaldehyde 32 A" 688 462 -226 1.488
C6H4O2 parabenzoquinone 16 B2g 794 619 -175 1.282
C6H4O2 parabenzoquinone 17 B2g 241 159 -82 1.518
C6H4O2 parabenzoquinone 30 B3u 109 83 -25 1.304
CHCCH2CH3 1-Butyne 22 A" 630 521 -109 1.209
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.754
C6H5Cl chlorobenzene 18 B1 685 450 -234 1.520
C5H12 Pentane 23 A2 131 103 -28 1.276
C3H2N2 Malononitrile 6 A1 167 132 -35 1.267
C4H4N2 Succinonitrile 17 Bg 387 317 -70 1.220
C5H8 Cyclopentene 18 A' 254 173 -81 1.466
C5H8 Cyclopentene 29 A" 1082 901 -181 1.201
C2H3N3 1H-1,2,4-Triazole 14 A" 990 821 -169 1.206
C2H4O3 trioxolane124 21 B 193 160 -33 1.206
C4H4N2 Pyridazine 13 A2 421 334 -87 1.261
NH2CN cyanamide 5 A' 408 637 229 0.641
C4H6O2 2,3-Butanedione 21 Bg 240 111 -129 2.160
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.223
C4H2 Diacetylene 8 Πu 630 500 -130 1.259
C6H5F Fluorobenzene 18 B1 685 481 -204 1.425
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C2H3NO3 Oxamic acid 12 A' 687 569 -118 1.207
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 16 A" 984 751 -233 1.310
C2H3NO3 Oxamic acid 17 A" 815 646 -169 1.262
C2H3NO3 Oxamic acid 18 A" 745 600 -145 1.241
C2H3NO3 Oxamic acid 19 A" 481 400 -81 1.203
C2H3NO3 Oxamic acid 21 A" 162 53 -109 3.053
CH3CCCH3 2-Butyne 16 E" 371 214 -157 1.730
C3O2 Carbon suboxide 7 Πu 61 100 39 0.611
C6H4F2 1,4-difluorobenzene 16 B2g 692 455 -237 1.520
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C5H8 1,4-Pentadiene 17 A 102 82 -20 1.247
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.351
C6H10 1,5-Hexadiene 29 Bg 264 162 -102 1.632
COBr2 Carbonic dibromide 6 B2 512 321 -191 1.594
COBr2 Carbonic dibromide 4 B1 757 486 -271 1.558
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.263
C6H8 1,4-Cyclohexadiene 19 B1u 108 75 -33 1.447
C6H8 1,4-Cyclohexadiene 23 B2g 403 326 -77 1.235
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CH2D2 methane-d2 6 B1 3013 2274 -739 1.325
CH2D2 methane-d2 8 B2 2234 3070 836 0.728
C2F2 difluoroacetylene 4 Πg 270 172 -98 1.566
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.234
C4N2 2-Butynedinitrile 3 Σg 692 569 -123 1.217
NaOH sodium hydroxide 3 Π 300 111 -189 2.699
GeO2 Germanium dioxide 3 Πu 196 153 -42 1.278
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.410
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.411
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.410
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.411
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.580
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.578
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.580
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.578
CH3OO methylperoxy radical 12 A" 170 123 -47 1.377
CN Cyano radical 1 Σ 2069 2681 612 0.772
C2H Ethynyl radical 2 Σ 1841 2327 486 0.791
C2H Ethynyl radical 3 Π 372 762 390 0.488
CH3 Methyl radical 2 A2" 606 366 -241 1.658
CH3 Methyl radical 2 A2" 606 366 -241 1.658
CH3 Methyl radical 2 A2" 606 366 -241 1.658
CH3 Methyl radical 2 A2" 606 366 -241 1.658
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 120 -144 2.192
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 89 -269 4.027
CH2OH Hydroxymethyl radical 8 A 482 736 254 0.655
CH2OH Hydroxymethyl radical 9 A 234 431 197 0.543
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 858 -278 1.324
CH2CHO Vinyloxy radical 10 A" 703 1010 307 0.696
BF3+ boron trifluoride cation 3 E' 1662 2138 477 0.777
C4H6 Methylenecyclopropane 17 B1 360 259 -101 1.390
C2Cl2+ dichloroacetylene cation 5 Πu 233 167 -66 1.395
ClFO3 Perchloryl fluoride 6 E 405 334 -71 1.212
O2+ diatomic oxygen cation 1 Σg 1906 1257 -649 1.516
O2+ diatomic oxygen cation 1 Σg 1906 1257 -649 1.516
O2+ diatomic oxygen cation 1 Σg 1906 1257 -649 1.516
O2+ diatomic oxygen cation 1 Σg 1906 1257 -649 1.516
MgF2 Magnesium fluoride 3 Πu 165 134 -31 1.232
SF4 Sulfur tetrafluoride 4 A1 228 186 -42 1.223
AsH3+ Arsine cation 2 A1 452 678 226 0.666
FOOF Perfluoroperoxide 1 A 1210 945 -265 1.281
BrF5 bromine pentafluoride 6 B2 281 212 -69 1.325
N2O3 Dinitrogen trioxide 7 A' 205 168 -37 1.221
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.385
PCl5 Phosphorus pentachloride 2 A1' 370 277 -93 1.336
O3 Ozone 3 B2 1042 2228 1186 0.468
NO Nitric oxide 1 Σ 1904 3665 1761 0.520
NO+ nitric oxide cation 1 Σ 2377 1980 -397 1.200
NO2 Nitrogen dioxide 3 B2 1618 2127 509 0.761
PS phosphorus sulfide 1 Σ 739 1172 433 0.631
NS+ nitrogen sulfide cation 1 Σ 1415 1154 -261 1.226
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
C3 carbon trimer 3 Πu 63 165 101 0.385
C5H5- cylopentadienyl anion 8 E1" 625 515 -110 1.212
C5H5- cylopentadienyl anion 14 E2" 600 489 -111 1.226
N2O4 Dinitrogen tetroxide 9 B2u 265 180 -85 1.471
Cu2 Copper dimer 1 Σg 265 380 115 0.697
Li2O dilithium oxide 3 Πu 112 61 -50 1.824
ClNO2 Nitryl chloride 3 A1 364 299 -64 1.215
CaOH Calcium monohydroxide 2 Σ 353 598 245 0.590
CaOH Calcium monohydroxide 3 Π 609 377 -232 1.614
ZnH2 Zinc hydride 3 Πu 633 476 -156 1.328
PO Phosphorus monoxide 1 Σ 1233 3842 2608 0.321
PO Phosphorus monoxide 1 Σ 1233 3842 2609 0.321
PO Phosphorus monoxide 1 Σ 1233 3842 2608 0.321
PO Phosphorus monoxide 1 Σ 1233 3842 2609 0.321
SiH- silicon monohydride anion 1 Σ 2175 1808 -367 1.203
SiH- silicon monohydride anion 1 Σ 2175 1808 -367 1.203
SiH- silicon monohydride anion 1 Σ 2175 1808 -367 1.203
SiH- silicon monohydride anion 1 Σ 2175 1808 -367 1.203
SF5Cl sulfur chloropentafluoride 7 B2 505 301 -204 1.681
SF5Cl sulfur chloropentafluoride 11 E 397 237 -160 1.675
ClOO chloroperoxy radical 2 A' 414 1023 609 0.404
ClOO chloroperoxy radical 3 A' 201 465 264 0.433
PN Phosphorus mononitride 1 Σ 1337 1079 -258 1.239
AlO Aluminum monoxide 1 Σ 979 719 -260 1.362
SF5Cl sulfur chloropentafluoride 5 B1 625 441 -184 1.417
FO2 Dioxygen monofluoride 1 A' 1487 2752 1265 0.540
FO2 Dioxygen monofluoride 2 A' 579 1172 592 0.494
FO2 Dioxygen monofluoride 3 A' 376 620 244 0.607
SCN thiocyanato radical 1 Σ 1942 2398 455 0.810
H2POH Phosphinous acid 9 A" 375 255 -121 1.474
ZnCH3 Zinc monomethyl 6 E 315 598 283 0.527
NCO isocyanato radical 1 Σ 1921 2349 428 0.818
GeH2 germylene 1 A1 1856 932 -924 1.992
GeH2 germylene 2 A1 916 1978 1062 0.463
NNS Nitrogen sulfide 1 Σ 2048 1695 -353 1.208
ONONO Nitrosyl nitrite 9 B2 380 257 -123 1.478
AsN Arsenic mononitride 1 Σ 1069 818 -250 1.306
Mg2 Magnesium diatomic 1 Σg 51 318 267 0.161
Mg2 Magnesium diatomic 1 Σg 51 318 267 0.161
Mg2 Magnesium diatomic 1 Σg 51 318 267 0.161
Mg2 Magnesium diatomic 1 Σg 51 318 267 0.161