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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 MP3/6-31G*
Calculated values were scaled by 0.9386.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 167 54 0.676
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.214
C6H6 Benzene 8 B2g 703 515 -188 1.366
C2H2 Acetylene 4 Πg 612 409 -203 1.496
HCN+ hydrogen cyanide cation 1 Σ 3050 3518 468 0.867
HCN+ hydrogen cyanide cation 2 Σ 1800 2715 915 0.663
CH3CCH propyne 9 E 633 517 -116 1.223
CH3CCH propyne 10 E 328 254 -74 1.290
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.224
CBr2F2 Methane, dibromodifluoro- 3 A1 140 321 181 0.437
C3F8 perfluoropropane 13 A2 276 213 -63 1.296
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 526 -106 1.203
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.312
CH3COOCH3 methyl acetate 27 A" 110 80 -30 1.382
C6H5NO2 Nitrobenzene 22 B1 675 511 -164 1.321
C10H8 naphthalene 12 Au 581 483 -98 1.202
C10H8 naphthalene 27 B2g 770 422 -348 1.825
C10H8 naphthalene 28 B2g 461 310 -151 1.486
C6H5CN phenyl cyanide 19 B1 688 546 -142 1.261
C6H4O2 parabenzoquinone 17 B2g 241 185 -56 1.304
C6H4O2 parabenzoquinone 30 B3u 109 86 -23 1.269
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.780
C5H12 Pentane 23 A2 131 103 -28 1.276
C6H5Cl chlorobenzene 18 B1 685 509 -176 1.345
C3H2N2 Malononitrile 6 A1 167 136 -31 1.231
C5H8 Cyclopentene 18 A' 254 157 -97 1.622
C2H3N3 1H-1,2,4-Triazole 18 A" 640 520 -120 1.230
C4H4N2 Pyridazine 13 A2 421 346 -75 1.216
C4H6O2 2,3-Butanedione 21 Bg 240 122 -118 1.974
C2H3NO3 Oxamic acid 15 A' 328 263 -65 1.246
C2H3NO3 Oxamic acid 16 A" 984 769 -215 1.280
C2H3NO3 Oxamic acid 17 A" 815 642 -173 1.269
C2H3NO3 Oxamic acid 18 A" 745 594 -151 1.255
C2H3NO3 Oxamic acid 20 A" 315 239 -76 1.319
C2H3NO3 Oxamic acid 21 A" 162 40 -122 4.049
NH2CN cyanamide 5 A' 408 643 235 0.635
C6H5F Fluorobenzene 18 B1 685 521 -164 1.316
C4H2 Diacetylene 7 Πg 482 294 -188 1.638
C4H2 Diacetylene 8 Πu 630 487 -143 1.293
C2H3NO3 Oxamic acid 3 A' 2600 3442 842 0.755
CH3CCCH3 2-Butyne 16 E" 371 218 -153 1.703
C6H4F2 1,4-difluorobenzene 16 B2g 692 516 -176 1.342
C5H8 1,4-Pentadiene 16 A 137 287 150 0.478
C5H8 1,4-Pentadiene 17 A 102 82 -20 1.243
C6H10 1,5-Hexadiene 14 Ag 351 261 -90 1.343
C6H10 1,5-Hexadiene 29 Bg 264 161 -103 1.635
COBr2 Carbonic dibromide 4 B1 757 493 -264 1.537
COBr2 Carbonic dibromide 6 B2 512 334 -178 1.535
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.276
CH2D2 methane-d2 6 B1 3013 2245 -768 1.342
CH2D2 methane-d2 8 B2 2234 3030 796 0.737
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.214
GeO2 Germanium dioxide 3 Πu 196 158 -38 1.240
NaOH sodium hydroxide 3 Π 300 171 -129 1.757
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.668
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 332 -124 1.375
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.558
C2H Ethynyl radical 3 Π 372 734 362 0.507
C2H Ethynyl radical 2 Σ 1841 2260 420 0.814
CN Cyano radical 1 Σ 2069 2516 447 0.822
C2H5 Ethyl radical 9 A' 528 434 -94 1.217
CH3 Methyl radical 2 A2" 606 395 -212 1.536
CH3 Methyl radical 2 A2" 606 395 -212 1.536
CH3 Methyl radical 2 A2" 606 395 -212 1.536
CH3 Methyl radical 2 A2" 606 395 -212 1.536
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 86 -272 4.172
CH2OH Hydroxymethyl radical 8 A 482 713 231 0.676
CH2OH Hydroxymethyl radical 9 A 234 416 182 0.562
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 859 -277 1.323
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 118 -146 2.235
OH- hydroxide anion 1 Σ 3738 3312 -426 1.129
C2Cl2 dichloroacetylene 4 Πg 333 202 -131 1.650
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.347
BF3+ boron trifluoride cation 3 E' 1662 2111 450 0.787
C2Cl2+ dichloroacetylene cation 5 Πu 233 170 -63 1.372
MgF2 Magnesium fluoride 3 Πu 165 135 -30 1.220
FOOF Perfluoroperoxide 1 A 1210 957 -253 1.264
ZnCN Zinc monocyanide 3 Π 212 80 -132 2.637
BrF5 bromine pentafluoride 6 B2 281 226 -55 1.242
PCl5 Phosphorus pentachloride 2 A1' 370 278 -92 1.331
O3 Ozone 3 B2 1042 1694 652 0.615
N2O3 Dinitrogen trioxide 9 A" 63 130 67 0.484
C3 carbon trimer 3 Πu 63 93 30 0.682
C3 carbon trimer 3 Πu 63 93 30 0.682
C3 carbon trimer 3 Πu 63 93 30 0.682
C3 carbon trimer 3 Πu 63 93 30 0.682
NO Nitric oxide 1 Σ 1904 2971 1067 0.641
ZnH2 Zinc hydride 3 Πu 633 487 -145 1.298
AlO Aluminum monoxide 1 Σ 979 756 -223 1.295
SiH- silicon monohydride anion 1 Σ 2175 1756 -419 1.239
SiH- silicon monohydride anion 1 Σ 2175 1755 -420 1.239
SiH- silicon monohydride anion 1 Σ 2175 1756 -419 1.239
SiH- silicon monohydride anion 1 Σ 2175 1755 -420 1.239
SF5Cl sulfur chloropentafluoride 7 B2 505 310 -195 1.629
SF5Cl sulfur chloropentafluoride 11 E 397 243 -154 1.636
PO Phosphorus monoxide 1 Σ 1233 2725 1492 0.453
PO Phosphorus monoxide 1 Σ 1233 2725 1492 0.453
PO Phosphorus monoxide 1 Σ 1233 2725 1492 0.453
PO Phosphorus monoxide 1 Σ 1233 2725 1492 0.453
SF5Cl sulfur chloropentafluoride 5 B1 625 452 -173 1.383
FO2 Dioxygen monofluoride 2 A' 579 74 -505 7.828
FO2 Dioxygen monofluoride 3 A' 376 36 -340 10.330
GeH2 germylene 1 A1 1856 893 -963 2.078
GeH2 germylene 2 A1 916 1740 824 0.526
ZnCH3 Zinc monomethyl 6 E 315 597 282 0.527
ClOO chloroperoxy radical 2 A' 414 1010 596 0.410
ClOO chloroperoxy radical 3 A' 201 466 265 0.432
PN+ phosphorus nitride cation 1 Σ 1200 2379 1179 0.504
H2POH Phosphinous acid 9 A" 375 254 -122 1.480
Cl3- trichloride anion 2 Σu 327 246 -81 1.328
ONONO Nitrosyl nitrite 9 B2 380 590 210 0.644
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.945
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.945
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.945
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.945