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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-121G*
Calculated values were scaled by 0.9528.

Species Name mode Symmetry Experiment Theory difference ratio
CH3CONH2 Acetamide 20 A 259 390 131 0.663
CH3COOH Acetic acid 11 A' 657 547 -110 1.201
CH3COOH Acetic acid 18 A" 93 52 -41 1.790
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3OH Methyl alcohol 12 A" 200 337 137 0.594
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3OH Methyl alcohol 12 A" 200 337 137 0.594
C2H6O2S Dimethyl sulfone 20 B1 262 212 -50 1.238
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 323 109 0.663
C2H4 Ethylene 7 B2g 940 773 -167 1.215
C2H2 Acetylene 4 Πg 612 335 -277 1.826
HCN+ hydrogen cyanide cation 1 Σ 3050 3809 759 0.801
HCN+ hydrogen cyanide cation 2 Σ 1800 2794 994 0.644
CH3CCH propyne 9 E 633 499 -134 1.268
CH2CCl2 Ethene, 1,1-dichloro- 7 B1 875 720 -155 1.215
N(CH3)3 Trimethylamine 11 A2 255 206 -49 1.235
C3F8 perfluoropropane 13 A2 276 214 -62 1.287
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.219
CH3COOCH3 methyl acetate 27 A" 110 17 -93 6.561
C9H8 Indene 35 A" 926 749 -177 1.236
C9H8 Indene 36 A" 917 721 -197 1.273
C9H8 Indene 37 A" 854 700 -154 1.220
C9H8 Indene 40 A" 690 443 -247 1.557
C9H8 Indene 41 A" 549 313 -236 1.754
C9H8 Indene 42 A" 415 302 -112 1.371
C9H8 Indene 43 A" 388 187 -201 2.076
C9H8 Indene 44 A" 206 169 -38 1.223
C9H8 Indene 45 A" 189 -689 -877 -0.274
C6H4O2 parabenzoquinone 16 B2g 794 496 -298 1.602
C6H4O2 parabenzoquinone 17 B2g 241 -302 -543 -0.799
C6H4O2 parabenzoquinone 30 B3u 109 75 -34 1.454
C3H6O 2-Propen-1-ol 24 A 188 105 -83 1.789
C5H12 Pentane 23 A2 131 92 -39 1.430
C3H2N2 Malononitrile 6 A1 167 130 -37 1.283
C4H5N Pyrrole 10 A2 864 674 -190 1.281
C4H5N Pyrrole 11 A2 692 574 -118 1.206
C4H5N Pyrrole 12 A2 614 407 -207 1.507
C4H4O Furan 9 A2 838 675 -163 1.242
C4H4O Furan 11 A2 603 385 -218 1.566
C4H4S Thiophene 9 A2 867 714 -153 1.214
C4H4S Thiophene 11 A2 567 418 -149 1.358
C4H4N2 Succinonitrile 17 Bg 387 309 -78 1.252
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 140 -53 1.379
C2Cl4 Tetrachloroethylene 4 Au 110 89 -21 1.231
C2Cl4 Tetrachloroethylene 7 B2g 512 344 -168 1.490
C5H8 Cyclopentene 18 A' 254 175 -79 1.451
C5H8 Cyclopentene 29 A" 1082 897 -185 1.207
C2H3N3 1H-1,2,4-Triazole 14 A" 990 790 -200 1.253
C2H3N3 1H-1,2,4-Triazole 15 A" 885 726 -159 1.219
C2H3N3 1H-1,2,4-Triazole 18 A" 640 509 -131 1.257
C4H4N2 Pyridazine 12 A2 751 433 -318 1.735
C4H4N2 Pyridazine 13 A2 421 217 -204 1.937
C4H4N2 Pyrazine 6 Au 960 798 -162 1.204
NH2CN cyanamide 5 A' 408 731 323 0.558
C4H6O2 2,3-Butanedione 9 Ag 614 498 -116 1.233
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.218
C4H2 Diacetylene 6 Πg 627 1132 505 0.554
CH2CO Ketene 6 B1 528 396 -132 1.332
C6H6 Fulvene 14 A2 666 555 -111 1.201
C6H6 Fulvene 15 A2 494 370 -124 1.335
C6H6 Fulvene 17 B1 907 744 -163 1.220
C3O2 Carbon suboxide 7 Πu 61 169 108 0.360
C6H4F2 1,4-difluorobenzene 7 Au 945 767 -178 1.232
C6H4F2 1,4-difluorobenzene 15 B2g 928 750 -178 1.238
C6H4F2 1,4-difluorobenzene 16 B2g 692 385 -307 1.796
C6H4F2 1,4-difluorobenzene 18 B2g 374 -292 -666 -1.282
C5H8 1,4-Pentadiene 16 A 137 289 152 0.474
C5H8 1,4-Pentadiene 17 A 102 81 -21 1.255
C6H10 1,5-Hexadiene 14 Ag 351 261 -90 1.346
C6H10 1,5-Hexadiene 20 Au 649 532 -117 1.221
C6H10 1,5-Hexadiene 29 Bg 264 137 -127 1.926
C5H6S Thiophene, 3-methyl- 27 A" 594 429 -165 1.386
CH3SSCH3 Disulfide, dimethyl 13 A 117 86 -31 1.363
CO+ carbon monoxide cation 1 Σ 2214 2714 500 0.816
CO+ carbon monoxide cation 1 Σ 2214 2714 500 0.816
CO+ carbon monoxide cation 1 Σ 2214 2714 500 0.816
CO+ carbon monoxide cation 1 Σ 2214 2714 500 0.816
CH2D2 methane-d2 6 B1 3013 2264 -749 1.331
CH2D2 methane-d2 8 B2 2234 3057 823 0.731
C2F2 difluoroacetylene 4 Πg 270 104 -166 2.603
C4H2N2 Fumaronitrile 18 Bu 148 121 -27 1.219
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 173 -44 1.251
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 137 -33 1.238
C4H6 Cyclobutene 13 A2 325 267 -58 1.218
C4N2 2-Butynedinitrile 3 Σg 692 563 -129 1.229
C4H4 cyclobutadiene 11 B2g 531 426 -105 1.246
LiOH lithium hydroxide 3 Π 257 385 129 0.665
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 305 -151 1.497
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 305 -151 1.496
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 102 -69 1.671
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 103 -68 1.665
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 305 -151 1.497
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 305 -151 1.496
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 102 -69 1.671
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 103 -68 1.665
C2H5 Ethyl radical 9 A' 528 437 -91 1.207
CN Cyano radical 1 Σ 2069 2661 592 0.777
C6H5O phenoxy radical 19 B1 472 175 -297 2.692
C2H Ethynyl radical 2 Σ 1841 2307 466 0.798
C2H Ethynyl radical 3 Π 372 785 413 0.474
C2H+ Ethynyl cation 3 Π 550 802 253 0.685
CH3OO methylperoxy radical 12 A" 170 126 -44 1.354
CH3 Methyl radical 2 A2" 606 404 -202 1.500
CH3 Methyl radical 2 A2" 606 404 -202 1.500
CH3 Methyl radical 2 A2" 606 404 -202 1.500
CH3 Methyl radical 2 A2" 606 404 -202 1.500
C6H5 phenyl 17 B1 655 452 -203 1.448
C6H5 phenyl 18 B1 415 150 -265 2.768
CH2OH Hydroxymethyl radical 8 A 482 758 276 0.636
CH2OH Hydroxymethyl radical 9 A 234 448 214 0.522
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 854 -282 1.330
C6H8 1,3,5-Hexatriene, (Z)- 17 A2 709 569 -140 1.245
C6H8 1,3,5-Hexatriene, (Z)- 18 A2 331 248 -83 1.334
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 103 -161 2.570
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 88 -270 4.068
HCCF Fluoroacetylene 5 Π 367 302 -65 1.215
CCl3 Trichloromethyl radical 2 A1 251 366 115 0.685
CH2CHO Vinyloxy radical 12 A" 404 321 -83 1.259
C4H6 Methylenecyclopropane 17 B1 360 253 -107 1.423
C2Cl2+ dichloroacetylene cation 4 Πg 318 264 -53 1.202
C2Cl2+ dichloroacetylene cation 5 Πu 233 179 -54 1.301
ClFO3 Perchloryl fluoride 2 A1 715 596 -119 1.200
ClFO3 Perchloryl fluoride 3 A1 549 441 -108 1.244
ClFO3 Perchloryl fluoride 6 E 405 314 -91 1.288
BF3+ boron trifluoride cation 3 E' 1662 2119 458 0.784
O2+ diatomic oxygen cation 1 Σg 1906 1217 -689 1.566
O2+ diatomic oxygen cation 1 Σg 1906 1217 -689 1.566
O2+ diatomic oxygen cation 1 Σg 1906 1217 -689 1.566
O2+ diatomic oxygen cation 1 Σg 1906 1217 -689 1.566
MgF2 Magnesium fluoride 3 Πu 165 116 -49 1.419
FOOF Perfluoroperoxide 1 A 1210 996 -214 1.215
FNO3 Fluorine nitrate 6 A' 455 378 -77 1.205
PCl5 Phosphorus pentachloride 2 A1' 370 285 -85 1.300
O3 Ozone 3 B2 1042 2339 1297 0.445
NO Nitric oxide 1 Σ 1904 3905 2001 0.488
NO+ nitric oxide cation 1 Σ 2377 1924 -453 1.236
NO2 Nitrogen dioxide 3 B2 1618 2040 422 0.793
N2O4 Dinitrogen tetroxide 9 B2u 265 177 -88 1.501
N2O3 Dinitrogen trioxide 7 A' 205 170 -35 1.208
N2O3 Dinitrogen trioxide 9 A" 63 150 87 0.421
NS+ nitrogen sulfide cation 1 Σ 1415 1145 -270 1.236
Li2O dilithium oxide 3 Πu 112 83 -29 1.345
FO Oxygen monofluoride 1 Σ 1053 1534 481 0.686
FO Oxygen monofluoride 1 Σ 1053 2267 1214 0.464
FO Oxygen monofluoride 1 Σ 1053 1534 481 0.686
FO Oxygen monofluoride 1 Σ 1053 2267 1214 0.464
C3 carbon trimer 3 Πu 63 308 244 0.206
C3 carbon trimer 3 Πu 63 308 244 0.206
C3 carbon trimer 3 Πu 63 308 244 0.206
C3 carbon trimer 3 Πu 63 308 244 0.206
C5H5- cylopentadienyl anion 4 A2" 710 590 -120 1.204
C5H5- cylopentadienyl anion 8 E1" 625 416 -209 1.503
C5H5- cylopentadienyl anion 14 E2" 600 104 -496 5.751
MgOH magnesium hydroxide 3 Π 188 65 -123 2.907
C4 Carbon tetramer 4 Πg 323 523 200 0.617
PS phosphorus sulfide 1 Σ 739 1143 404 0.647
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
SF5Cl sulfur chloropentafluoride 5 B1 625 437 -188 1.429
SF5Cl sulfur chloropentafluoride 7 B2 505 301 -204 1.680
SF5Cl sulfur chloropentafluoride 11 E 397 236 -161 1.681
PO Phosphorus monoxide 1 Σ 1233 5220 3987 0.236
PO Phosphorus monoxide 1 Σ 1233 5217 3984 0.236
PO Phosphorus monoxide 1 Σ 1233 5220 3987 0.236
PO Phosphorus monoxide 1 Σ 1233 5217 3984 0.236
PO+ phosphorus monoxide cation 1 Σ 1405 1165 -240 1.206
AlO Aluminum monoxide 1 Σ 979 589 -390 1.662
ClONO2 Chlorine nitrate 6 A' 434 361 -73 1.201
SCN thiocyanato radical 1 Σ 1942 2459 517 0.790
ClOO chloroperoxy radical 2 A' 414 1024 610 0.404
ClOO chloroperoxy radical 3 A' 201 466 265 0.432
PN Phosphorus mononitride 1 Σ 1337 1069 -268 1.251
B2H6 Diborane 11 B2g 850 701 -149 1.212
NCO isocyanato radical 1 Σ 1921 2353 432 0.816
H2POH Phosphinous acid 9 A" 375 251 -124 1.496
Mg2 Magnesium diatomic 1 Σg 51 31 -20 1.666
Mg2 Magnesium diatomic 1 Σg 51 31 -20 1.666
Mg2 Magnesium diatomic 1 Σg 51 31 -20 1.666
Mg2 Magnesium diatomic 1 Σg 51 31 -20 1.666
NNS Nitrogen sulfide 1 Σ 2048 1640 -407 1.248
ONONO Nitrosyl nitrite 9 B2 380 240 -140 1.585