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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 MP2FC/CEP-31G*
Calculated values were scaled by 0.9494.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 164 51 0.689
CH3COOH Acetic acid 11 A' 657 545 -112 1.204
CH3COOH Acetic acid 18 A" 93 70 -23 1.320
CH3OH Methyl alcohol 12 A" 200 324 124 0.617
CH3COCH3 Acetone 12 A2 77 39 -38 1.996
C2H6O2S Dimethyl sulfone 20 B1 262 199 -63 1.314
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 307 93 0.697
C2H4 Ethylene 7 B2g 940 730 -210 1.288
CH3NH2 methyl amine 14 A" 1195 930 -265 1.285
HCN+ hydrogen cyanide cation 1 Σ 3050 3903 853 0.781
HCN+ hydrogen cyanide cation 2 Σ 1800 2827 1027 0.637
CH2CHF Ethene, fluoro- 11 A" 863 715 -148 1.206
CH3NO2 Methane, nitro- 11 A" 1583 3085 1502 0.513
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 514 -118 1.230
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 59 -16 1.278
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.188
C6H4O2 parabenzoquinone 30 B3u 109 89 -19 1.213
C3H6O 2-Propen-1-ol 21 A 554 418 -136 1.327
C3H6O 2-Propen-1-ol 24 A 188 102 -86 1.843
C5H12 Pentane 23 A2 131 105 -26 1.252
C3H2N2 Malononitrile 6 A1 167 130 -37 1.288
C4H8O Furan, tetrahydro- 33 B 137 36 -101 3.800
C4H4N2 Succinonitrile 17 Bg 387 308 -79 1.258
C2F4 Tetrafluoroethylene 7 B2g 508 404 -104 1.256
C5H8 Cyclopentene 18 A' 254 187 -67 1.355
C5H8 Cyclopentene 29 A" 1082 898 -184 1.205
C5H8 Spiropentane 8 A2 919 721 -198 1.275
C5H8 Spiropentane 25 E 308 253 -55 1.216
C5H8 Bicyclo[2.1.0]pentane 33 A" 276 230 -46 1.200
C3H3NO Isoxazole 14 A" 1033 823 -210 1.255
C2H4O3 trioxolane124 21 B 193 160 -33 1.209
C4H4N2 Pyridazine 13 A2 421 345 -76 1.220
NH2CN cyanamide 5 A' 408 711 303 0.574
C4H6O2 2,3-Butanedione 9 Ag 614 496 -118 1.237
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.021
CH2CO Ketene 6 B1 528 317 -211 1.665
C2H3NO3 Oxamic acid 3 A' 2600 3435 835 0.757
C2H3NO3 Oxamic acid 12 A' 687 568 -119 1.210
C2H3NO3 Oxamic acid 15 A' 328 251 -77 1.307
C2H3NO3 Oxamic acid 16 A" 984 772 -212 1.274
C2H3NO3 Oxamic acid 17 A" 815 647 -168 1.259
C2H3NO3 Oxamic acid 18 A" 745 598 -147 1.245
C2H3NO3 Oxamic acid 20 A" 315 194 -121 1.621
C2H3NO3 Oxamic acid 21 A" 162 25 -137 6.363
CH3CCCH3 2-Butyne 16 E" 371 173 -198 2.144
C3O2 Carbon suboxide 7 Πu 61 182 121 0.334
CH2CHOH ethenol 13 A" 817 667 -150 1.224
C6H12 2-Butene, 2,3-dimethyl- 12 Au 182 145 -37 1.254
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 317 136 0.571
C5H8 1,4-Pentadiene 15 A 421 349 -72 1.205
C5H8 1,4-Pentadiene 16 A 137 283 146 0.484
C5H8 1,4-Pentadiene 17 A 102 78 -24 1.301
C5H8 1,4-Pentadiene 31 B 721 567 -154 1.272
C5H8 1,4-Pentadiene 33 B 331 82 -249 4.051
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.348
C6H10 1,5-Hexadiene 29 Bg 264 146 -118 1.805
C3H8O2S (Methylsulphonyl)ethane 32 ?a 324 267 -57 1.215
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 188 -39 1.210
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.270
C6H8 1,4-Cyclohexadiene 19 B1u 108 87 -21 1.246
C6H8 1,4-Cyclohexadiene 23 B2g 403 335 -68 1.204
CO+ carbon monoxide cation 1 Σ 2214 2766 552 0.801
C3H6O2 1,3-Dioxolane 4 A 1509 2949 1440 0.512
C3H6O2 1,3-Dioxolane 5 A 1480 2929 1449 0.505
C3H6O2 1,3-Dioxolane 6 A 1361 2884 1523 0.472
C3H6O2 1,3-Dioxolane 13 A 658 1215 557 0.541
C6H10 2-Hexyne 23 A' 359 298 -61 1.203
C6H10 2-Hexyne 24 A' 272 206 -66 1.322
C6H10 2-Hexyne 25 A' 115 78 -37 1.483
C6H10 2-Hexyne 38 A" 392 227 -165 1.726
C6H10 2-Hexyne 41 A" 88 73 -15 1.211
C4H2N2 Fumaronitrile 18 Bu 148 120 -28 1.234
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.247
C4H6 Cyclobutene 13 A2 325 258 -67 1.257
C4N2 2-Butynedinitrile 3 Σg 692 559 -133 1.238
LiOH lithium hydroxide 3 Π 257 381 124 0.674
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.387
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 128 -43 1.336
C5H8 1,3-Pentadiene, (E)- 31 A" 361 242 -119 1.491
C5H8 1,3-Pentadiene, (E)- 32 A" 129 198 69 0.651
C2H5 Ethyl radical 9 A' 528 428 -100 1.233
CN Cyano radical 1 Σ 2069 2634 565 0.785
C2H Ethynyl radical 3 Π 372 789 417 0.471
C2H+ Ethynyl cation 3 Π 550 804 254 0.684
CH3 Methyl radical 2 A2" 606 403 -204 1.506
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 853 -283 1.331
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 148 -116 1.785
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 105 -253 3.409
HCCF Fluoroacetylene 5 Π 367 272 -95 1.349
CCl3 Trichloromethyl radical 2 A1 251 362 111 0.693
CH2CHO Vinyloxy radical 12 A" 404 317 -87 1.276
C4H6 Methylenecyclopropane 17 B1 360 270 -90 1.332
C2Cl2 dichloroacetylene 4 Πg 333 275 -58 1.213
C2Cl2+ dichloroacetylene cation 5 Πu 233 183 -50 1.272
ClFO3 Perchloryl fluoride 3 A1 549 443 -106 1.239
ClFO3 Perchloryl fluoride 5 E 589 487 -102 1.211
ClFO3 Perchloryl fluoride 6 E 405 325 -80 1.246
BF3+ boron trifluoride cation 3 E' 1662 2119 457 0.784
O2+ diatomic oxygen cation 1 Σg 1906 1226 -680 1.555
PCl5 Phosphorus pentachloride 2 A1' 370 283 -87 1.308
PCl5 Phosphorus pentachloride 7 E' 100 83 -17 1.203
O3 Ozone 3 B2 1042 2343 1300 0.445
NO Nitric oxide 1 Σ 1904 4209 2305 0.452
NO+ nitric oxide cation 1 Σ 2377 1944 -433 1.223
NO2 Nitrogen dioxide 3 B2 1618 2036 418 0.795
N2O4 Dinitrogen tetroxide 9 B2u 265 179 -86 1.484
N2O3 Dinitrogen trioxide 7 A' 205 167 -38 1.227
N2O3 Dinitrogen trioxide 9 A" 63 154 91 0.410
NS+ nitrogen sulfide cation 1 Σ 1415 1128 -287 1.255
FO Oxygen monofluoride 1 Σ 1053 1536 483 0.685
C3 carbon trimer 3 Πu 63 295 232 0.215
MgOH magnesium hydroxide 3 Π 188 116 -72 1.616
C4 Carbon tetramer 4 Πg 323 555 232 0.582
SiH- silicon monohydride anion 1 Σ 2175 1757 -418 1.238
PO Phosphorus monoxide 1 Σ 1233 5336 4103 0.231
PO+ phosphorus monoxide cation 1 Σ 1405 1165 -240 1.206
AlO Aluminum monoxide 1 Σ 979 634 -345 1.544
SCN thiocyanato radical 1 Σ 1942 2441 498 0.796
ClOO chloroperoxy radical 2 A' 414 1025 611 0.404
ClOO chloroperoxy radical 3 A' 201 462 261 0.436
PN Phosphorus mononitride 1 Σ 1337 1063 -274 1.258
NCO isocyanato radical 1 Σ 1921 2412 490 0.797