return to home page

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
CH3CONH2 Acetamide 20 A 259 377 118 0.687
C2H6O2S Dimethyl sulfone 20 B1 262 214 -48 1.222
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 333 119 0.643
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
C6H6 Benzene 8 B2g 703 391 -312 1.798
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- 16 A' 632 523 -109 1.207
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 54 -21 1.381
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
C6H5CHO benzaldehyde 32 A" 688 411 -277 1.673
C6H4O2 parabenzoquinone 30 B3u 109 82 -27 1.327
C6H5CN phenyl cyanide 19 B1 688 531 -157 1.297
C6H5CN phenyl cyanide 20 B1 542 440 -102 1.232
C6H4O2 parabenzoquinone 16 B2g 794 659 -135 1.204
C6H4O2 parabenzoquinone 17 B2g 241 147 -94 1.635
C6H5Cl chlorobenzene 19 B1 467 380 -86 1.227
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.691
C6H5Cl chlorobenzene 18 B1 685 424 -261 1.615
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
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
C4H2 Diacetylene 7 Πg 482 375 -107 1.284
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
C6H4F2 1,4-difluorobenzene 16 B2g 692 530 -162 1.305
C5H8 1,4-Pentadiene 16 A 137 290 153 0.473
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.235
C6H10 1,5-Hexadiene 14 Ag 351 261 -90 1.344
C6H10 1,5-Hexadiene 20 Au 649 538 -111 1.207
C6H10 1,5-Hexadiene 29 Bg 264 156 -108 1.695
COBr2 Carbonic dibromide 6 B2 512 337 -175 1.517
COBr2 Carbonic dibromide 4 B1 757 500 -257 1.515
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
CaO Calcium monoxide 1 Σ 732 507 -225 1.444
C4H6 Cyclobutene 13 A2 325 262 -63 1.241
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
C4N2 2-Butynedinitrile 3 Σg 692 572 -120 1.211
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
CN Cyano radical 1 Σ 2069 2714 646 0.762
C2H Ethynyl radical 3 Π 372 801 429 0.464
C2H Ethynyl radical 2 Σ 1841 2349 508 0.784
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
CH3OO methylperoxy radical 12 A" 170 138 -32 1.236
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
C2Cl2 dichloroacetylene 4 Πg 333 177 -156 1.878
C4H6 Methylenecyclopropane 17 B1 360 261 -99 1.382
C2Cl2+ dichloroacetylene cation 5 Πu 233 183 -50 1.275
FOOF Perfluoroperoxide 3 A 360 233 -127 1.544
FOOF Perfluoroperoxide 4 A 202 129 -73 1.567
BF3+ boron trifluoride cation 3 E' 1662 2147 486 0.774
MgF2 Magnesium fluoride 3 Πu 165 137 -28 1.206
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
CaF2 Calcium difluoride 2 A1 120 59 -61 2.036
ZnCl Zinc monochloride 1 Σ 391 300 -91 1.303
NO Nitric oxide 1 Σ 1904 3351 1447 0.568
NO2 Nitrogen dioxide 3 B2 1618 2382 764 0.679
PCl5 Phosphorus pentachloride 2 A1' 370 266 -104 1.393
CaOH Calcium monohydroxide 2 Σ 353 621 269 0.568
CaOH Calcium monohydroxide 3 Π 609 353 -256 1.725
O3 Ozone 3 B2 1042 2156 1114 0.483
Li2O dilithium oxide 3 Πu 112 58 -53 1.912
FO Oxygen monofluoride 1 Σ 1053 2333 1280 0.451
FO Oxygen monofluoride 1 Σ 1053 2333 1280 0.451
N2O4 Dinitrogen tetroxide 9 B2u 265 196 -69 1.351
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.383
PS phosphorus sulfide 1 Σ 739 1290 551 0.573
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
ClNO2 Nitryl chloride 3 A1 364 280 -84 1.300
C5H5- cylopentadienyl anion 14 E2" 600 486 -114 1.234
SF5Cl sulfur chloropentafluoride 11 E 397 244 -153 1.628
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
SF5Cl sulfur chloropentafluoride 7 B2 505 309 -196 1.634
FO2 Dioxygen monofluoride 2 A' 579 68 -512 8.556
FO2 Dioxygen monofluoride 3 A' 376 29 -347 12.977
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
GeH2 germylene 1 A1 1856 947 -909 1.959
AlO Aluminum monoxide 1 Σ 979 745 -234 1.314
SCN thiocyanato radical 1 Σ 1942 2408 466 0.807
ClOO chloroperoxy radical 2 A' 414 1058 645 0.391
ClOO chloroperoxy radical 3 A' 201 488 286 0.413
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
F3- trifluoride anion 1 Σg 461 378 -83 1.220
AsN Arsenic mononitride 1 Σ 1069 827 -242 1.293
ONONO Nitrosyl nitrite 9 B2 380 221 -159 1.722
NCO isocyanato radical 1 Σ 1921 2354 433 0.816
ZnCH3 Zinc monomethyl 6 E 315 599 284 0.526
H2POH Phosphinous acid 9 A" 375 261 -114 1.435