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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/6-311G**
Calculated values were scaled by 0.9486.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
CH3COOH Acetic acid 18 A" 93 71 -22 1.302
CH3CONH2 Acetamide 20 A 259 377 118 0.687
C2H6O2S Dimethyl sulfone 20 B1 262 214 -48 1.222
C6H6 Benzene 8 B2g 703 391 -312 1.798
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 333 119 0.643
HCN+ hydrogen cyanide cation 1 Σ 3050 3663 613 0.833
HCN+ hydrogen cyanide cation 2 Σ 1800 2755 955 0.653
CBr2F2 Methane, dibromodifluoro- 3 A1 140 331 191 0.423
C3F8 perfluoropropane 13 A2 276 220 -56 1.253
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 54 -21 1.381
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.207
C9H8 Indene 40 A" 690 498 -192 1.387
C9H8 Indene 41 A" 549 376 -172 1.458
CH3COOCH3 methyl acetate 27 A" 110 38 -72 2.862
C6H5CN phenyl cyanide 19 B1 688 531 -157 1.297
C6H5CN phenyl cyanide 20 B1 542 440 -102 1.232
C6H5CHO benzaldehyde 32 A" 688 411 -277 1.673
C6H4O2 parabenzoquinone 16 B2g 794 659 -135 1.204
C6H4O2 parabenzoquinone 17 B2g 241 147 -94 1.635
C6H4O2 parabenzoquinone 30 B3u 109 82 -27 1.327
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.691
C6H5Cl chlorobenzene 18 B1 685 424 -261 1.615
C6H5Cl chlorobenzene 19 B1 467 380 -86 1.227
C5H12 Pentane 23 A2 131 91 -40 1.441
C3H2N2 Malononitrile 6 A1 167 137 -30 1.219
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 146 -47 1.320
C4H8O2 1,4-Dioxane 19 Au 288 235 -53 1.223
C5H8 Cyclopentene 18 A' 254 182 -72 1.398
C4H4N2 Pyridazine 13 A2 421 333 -88 1.264
C4H2 Diacetylene 7 Πg 482 375 -107 1.284
NH2CN cyanamide 5 A' 408 674 266 0.605
C4H6O2 2,3-Butanedione 9 Ag 614 507 -107 1.210
C4H6O2 2,3-Butanedione 13 Au 1111 919 -192 1.209
C4H6O2 2,3-Butanedione 21 Bg 240 121 -119 1.990
C6H4F2 1,4-difluorobenzene 16 B2g 692 530 -162 1.305
C6H5F Fluorobenzene 18 B1 685 504 -181 1.359
C6H5F Fluorobenzene 19 B1 500 416 -84 1.201
CH3CCCH3 2-Butyne 16 E" 371 275 -96 1.349
C6H10 1,5-Hexadiene 29 Bg 264 156 -108 1.695
C6H10 1,5-Hexadiene 20 Au 649 538 -111 1.207
C6H10 1,5-Hexadiene 14 Ag 351 261 -90 1.344
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.235
C5H8 1,4-Pentadiene 16 A 137 290 153 0.473
COBr2 Carbonic dibromide 4 B1 757 500 -257 1.515
COBr2 Carbonic dibromide 6 B2 512 337 -175 1.517
CO+ carbon monoxide cation 1 Σ 2214 2735 521 0.810
CO+ carbon monoxide cation 1 Σ 2214 2735 521 0.810
CO+ carbon monoxide cation 1 Σ 2214 2735 521 0.810
CO+ carbon monoxide cation 1 Σ 2214 2735 521 0.810
C6H8 1,4-Cyclohexadiene 19 B1u 108 65 -43 1.653
C6H8 1,4-Cyclohexadiene 23 B2g 403 309 -94 1.303
CH2D2 methane-d2 6 B1 3013 2262 -751 1.332
CH2D2 methane-d2 8 B2 2234 3054 820 0.731
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.232
C4H6 Cyclobutene 13 A2 325 262 -63 1.241
C4N2 2-Butynedinitrile 3 Σg 692 572 -120 1.211
CaO Calcium monoxide 1 Σ 732 507 -225 1.444
LiOH lithium hydroxide 3 Π 257 374 117 0.686
NaOH sodium hydroxide 3 Π 300 226 -74 1.326
ZnS Zinc sulfide 1 Σ 459 368 -91 1.246
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 321 -135 1.420
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 112 -59 1.520
CN Cyano radical 1 Σ 2069 2714 646 0.762
C2H Ethynyl radical 2 Σ 1841 2349 508 0.784
C2H Ethynyl radical 3 Π 372 801 429 0.464
CH3OO methylperoxy radical 12 A" 170 138 -32 1.236
CH3 Methyl radical 2 A2" 606 402 -204 1.508
CH3 Methyl radical 2 A2" 606 402 -204 1.508
CH3 Methyl radical 2 A2" 606 402 -204 1.508
CH3 Methyl radical 2 A2" 606 402 -204 1.508
CH2OH Hydroxymethyl radical 8 A 482 690 208 0.699
CH2OH Hydroxymethyl radical 9 A 234 442 208 0.530
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 855 -281 1.329
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 118 -146 2.229
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 88 -270 4.052
CH2CHO Vinyloxy radical 10 A" 703 1019 316 0.690
C4H6 Methylenecyclopropane 17 B1 360 261 -99 1.382
BF3+ boron trifluoride cation 3 E' 1662 2147 486 0.774
C2Cl2 dichloroacetylene 4 Πg 333 177 -156 1.878
C2Cl2+ dichloroacetylene cation 5 Πu 233 183 -50 1.275
O2+ diatomic oxygen cation 1 Σg 1906 1414 -492 1.348
O2+ diatomic oxygen cation 1 Σg 1906 1414 -492 1.348
O2+ diatomic oxygen cation 1 Σg 1906 1414 -492 1.348
O2+ diatomic oxygen cation 1 Σg 1906 1414 -492 1.348
FOOF Perfluoroperoxide 3 A 360 233 -127 1.544
FOOF Perfluoroperoxide 4 A 202 129 -73 1.567
MgF2 Magnesium fluoride 3 Πu 165 137 -28 1.206
CaF2 Calcium difluoride 2 A1 120 59 -61 2.036
O3 Ozone 3 B2 1042 2156 1114 0.483
ZnCl Zinc monochloride 1 Σ 391 300 -91 1.303
PCl5 Phosphorus pentachloride 2 A1' 370 266 -104 1.393
FO Oxygen monofluoride 1 Σ 1053 2333 1280 0.451
FO Oxygen monofluoride 1 Σ 1053 2333 1280 0.451
NO Nitric oxide 1 Σ 1904 3351 1447 0.568
NO2 Nitrogen dioxide 3 B2 1618 2382 764 0.679
CaOH Calcium monohydroxide 2 Σ 353 621 269 0.568
CaOH Calcium monohydroxide 3 Π 609 353 -256 1.725
N2O4 Dinitrogen tetroxide 9 B2u 265 196 -69 1.351
PS phosphorus sulfide 1 Σ 739 1290 551 0.573
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.383
Li2O dilithium oxide 3 Πu 112 58 -53 1.912
C3 carbon trimer 3 Πu 63 173 109 0.367
C3 carbon trimer 3 Πu 63 173 109 0.367
C3 carbon trimer 3 Πu 63 173 109 0.367
C3 carbon trimer 3 Πu 63 173 109 0.367
C5H5- cylopentadienyl anion 8 E1" 625 502 -123 1.244
C5H5- cylopentadienyl anion 14 E2" 600 486 -114 1.234
ClNO2 Nitryl chloride 3 A1 364 280 -84 1.300
SiH- silicon monohydride anion 1 Σ 2175 1809 -366 1.202
SiH- silicon monohydride anion 1 Σ 2175 1812 -363 1.201
SiH- silicon monohydride anion 1 Σ 2175 1809 -366 1.202
SiH- silicon monohydride anion 1 Σ 2175 1812 -363 1.201
SF5Cl sulfur chloropentafluoride 5 B1 625 457 -168 1.367
SCN thiocyanato radical 1 Σ 1942 2408 466 0.807
SF5Cl sulfur chloropentafluoride 7 B2 505 309 -196 1.634
SF5Cl sulfur chloropentafluoride 11 E 397 244 -153 1.628
PO Phosphorus monoxide 1 Σ 1233 3549 2316 0.348
PO Phosphorus monoxide 1 Σ 1233 3549 2316 0.348
PO Phosphorus monoxide 1 Σ 1233 3549 2316 0.348
PO Phosphorus monoxide 1 Σ 1233 3549 2316 0.348
AlO Aluminum monoxide 1 Σ 979 745 -234 1.314
FO2 Dioxygen monofluoride 2 A' 579 68 -512 8.556
FO2 Dioxygen monofluoride 3 A' 376 29 -347 12.977
F3- trifluoride anion 1 Σg 461 378 -83 1.220
AsN Arsenic mononitride 1 Σ 1069 827 -242 1.293
Mg2 Magnesium diatomic 1 Σg 51 29 -22 1.752
Mg2 Magnesium diatomic 1 Σg 51 29 -22 1.752
Mg2 Magnesium diatomic 1 Σg 51 29 -22 1.752
Mg2 Magnesium diatomic 1 Σg 51 29 -22 1.752
GeH2 germylene 1 A1 1856 947 -909 1.959
ClOO chloroperoxy radical 2 A' 414 1058 645 0.391
ClOO chloroperoxy radical 3 A' 201 488 286 0.413
NCO isocyanato radical 1 Σ 1921 2354 433 0.816
ZnCH3 Zinc monomethyl 6 E 315 599 284 0.526
ONONO Nitrosyl nitrite 9 B2 380 221 -159 1.722
H2POH Phosphinous acid 9 A" 375 261 -114 1.435