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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/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
CH3OH Methyl alcohol 12 A" 200 324 124 0.616
CH3OH Methyl alcohol 12 A" 200 324 124 0.617
CH3OH Methyl alcohol 12 A" 200 324 124 0.616
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
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
C3F8 perfluoropropane 13 A2 276 214 -62 1.292
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 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
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
C2H4O3 trioxolane124 21 B 193 160 -33 1.209
C4H4N2 Pyridazine 13 A2 421 345 -76 1.220
CH2CO Ketene 6 B1 528 317 -211 1.665
NH2CN cyanamide 5 A' 408 711 303 0.574
CH3CCCH3 2-Butyne 16 E" 371 173 -198 2.144
C3O2 Carbon suboxide 7 Πu 61 182 121 0.334
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.021
C4H6O2 2,3-Butanedione 9 Ag 614 496 -118 1.237
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
C2H3NO3 Oxamic acid 3 A' 2600 3435 835 0.757
CH2CHOH ethenol 13 A" 817 667 -150 1.224
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
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.348
C6H10 1,5-Hexadiene 29 Bg 264 146 -118 1.805
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 188 -39 1.210
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.270
C4H2N2 Fumaronitrile 18 Bu 148 120 -28 1.234
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
CO+ carbon monoxide cation 1 Σ 2214 2766 552 0.801
CO+ carbon monoxide cation 1 Σ 2214 2766 552 0.801
CO+ carbon monoxide cation 1 Σ 2214 2766 552 0.801
CH2D2 methane-d2 6 B1 3013 2264 -749 1.331
CH2D2 methane-d2 8 B2 2234 3056 822 0.731
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)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
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)- 31 A" 456 329 -127 1.386
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.387
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.386
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 128 -43 1.336
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 128 -43 1.332
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 128 -43 1.336
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 128 -43 1.332
C2H5 Ethyl radical 9 A' 528 428 -100 1.233
CN Cyano radical 1 Σ 2069 2634 565 0.785
CH3OO methylperoxy radical 12 A" 170 140 -30 1.215
C2H+ Ethynyl cation 3 Π 550 804 254 0.684
C2H Ethynyl radical 3 Π 372 789 417 0.471
CH3 Methyl radical 2 A2" 606 403 -204 1.506
CH3 Methyl radical 2 A2" 606 403 -204 1.506
CH3 Methyl radical 2 A2" 606 403 -204 1.506
CH3 Methyl radical 2 A2" 606 403 -204 1.506
CH2OH Hydroxymethyl radical 8 A 482 756 274 0.638
CH2OH Hydroxymethyl radical 9 A 234 435 201 0.538
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
O2+ diatomic oxygen cation 1 Σg 1906 1226 -680 1.555
O2+ diatomic oxygen cation 1 Σg 1906 1226 -680 1.555
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
FOOF Perfluoroperoxide 1 A 1210 984 -226 1.230
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
FO Oxygen monofluoride 1 Σ 1053 2262 1209 0.466
FO Oxygen monofluoride 1 Σ 1053 1536 483 0.685
FO Oxygen monofluoride 1 Σ 1053 2262 1209 0.466
MgOH magnesium hydroxide 3 Π 188 116 -72 1.616
C4 Carbon tetramer 4 Πg 323 555 232 0.582
PO Phosphorus monoxide 1 Σ 1233 5336 4103 0.231
PO Phosphorus monoxide 1 Σ 1233 5350 4117 0.231
PO Phosphorus monoxide 1 Σ 1233 5336 4103 0.231
PO Phosphorus monoxide 1 Σ 1233 5350 4117 0.231
PO+ phosphorus monoxide cation 1 Σ 1405 1165 -240 1.206
AlO Aluminum monoxide 1 Σ 979 634 -345 1.544
PN Phosphorus mononitride 1 Σ 1337 1063 -274 1.258
SiH- silicon monohydride anion 1 Σ 2175 1757 -418 1.238
SiH- silicon monohydride anion 1 Σ 2175 1757 -418 1.238
SiH- silicon monohydride anion 1 Σ 2175 1757 -418 1.238
SiH- silicon monohydride anion 1 Σ 2175 1757 -418 1.238
C3 carbon trimer 3 Πu 63 295 232 0.215
C3 carbon trimer 3 Πu 63 295 232 0.215
C3 carbon trimer 3 Πu 63 295 232 0.215
C3 carbon trimer 3 Πu 63 295 232 0.215
H2OH2O water dimer 8 A' 103 165 62 0.626
H2OH2O water dimer 11 A" 108 161 53 0.671
H2OH2O water dimer 12 A" 88 139 51 0.634
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
SF5Cl sulfur chloropentafluoride 5 B1 625 443 -182 1.410
SF5Cl sulfur chloropentafluoride 7 B2 505 305 -200 1.654
SF5Cl sulfur chloropentafluoride 11 E 397 242 -155 1.643
ONONO Nitrosyl nitrite 9 B2 380 293 -87 1.297
NCO isocyanato radical 1 Σ 1921 2412 490 0.797
H2POH Phosphinous acid 9 A" 375 258 -118 1.456
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.978
NNS Nitrogen sulfide 1 Σ 2048 1685 -362 1.215