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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 QCISD/6-31G*
Calculated values were scaled by 0.9523.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 328 128 0.610
CH3OH Methyl alcohol 12 A" 200 329 129 0.607
CH3OH Methyl alcohol 12 A" 200 328 128 0.610
CH3OH Methyl alcohol 12 A" 200 329 129 0.607
CH3COCH3 Acetone 12 A2 77 59 -18 1.316
C3H4O2 β–Propiolactone 21 A" 113 168 55 0.672
C6H6 Benzene 8 B2g 703 554 -149 1.268
CH3CCH propyne 9 E 633 514 -119 1.231
CH3CCH propyne 10 E 328 253 -75 1.295
C2H2 Acetylene 4 Πg 612 398 -214 1.537
CH3COCl Acetyl Chloride 15 A" 166 134 -32 1.235
CBr2F2 Methane, dibromodifluoro- 3 A1 140 323 183 0.434
C3F8 perfluoropropane 13 A2 276 215 -61 1.286
C9H8 Indene 40 A" 690 561 -129 1.231
CH3COOCH3 methyl acetate 27 A" 110 73 -37 1.504
C6H4O2 parabenzoquinone 30 B3u 109 83 -25 1.303
C6H5CHO benzaldehyde 32 A" 688 555 -133 1.240
C6H4O2 parabenzoquinone 17 B2g 241 183 -58 1.316
CHCCH2CH3 1-Butyne 22 A" 630 520 -110 1.211
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.781
C3H2N2 Malononitrile 6 A1 167 137 -30 1.219
C6H5Cl chlorobenzene 18 B1 685 545 -139 1.256
C5H8 Cyclopentene 18 A' 254 159 -95 1.597
NH2CN cyanamide 5 A' 408 659 251 0.619
C4H6O2 2,3-Butanedione 21 Bg 240 121 -119 1.977
C2H3NO3 Oxamic acid 15 A' 328 263 -65 1.245
C2H3NO3 Oxamic acid 16 A" 984 770 -214 1.279
C2H3NO3 Oxamic acid 17 A" 815 652 -163 1.250
C2H3NO3 Oxamic acid 18 A" 745 604 -141 1.234
C2H3NO3 Oxamic acid 20 A" 315 236 -79 1.335
C2H3NO3 Oxamic acid 21 A" 162 38 -124 4.304
C4H2 Diacetylene 7 Πg 482 332 -150 1.450
C4H2 Diacetylene 8 Πu 630 485 -145 1.299
C6H5F Fluorobenzene 18 B1 685 548 -137 1.249
C2H3NO3 Oxamic acid 3 A' 2600 3454 854 0.753
CH3CCCH3 2-Butyne 16 E" 371 226 -145 1.645
C6H4F2 1,4-difluorobenzene 16 B2g 692 539 -153 1.283
C5H8 1,4-Pentadiene 16 A 137 288 151 0.476
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.235
COBr2 Carbonic dibromide 4 B1 757 493 -264 1.535
COBr2 Carbonic dibromide 6 B2 512 330 -182 1.550
CH3ONO Methyl nitrite 15 A" 186 73 -113 2.532
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.253
CH2D2 methane-d2 6 B1 3013 2246 -767 1.341
CH2D2 methane-d2 8 B2 2234 3033 799 0.737
C2F2 difluoroacetylene 4 Πg 270 197 -73 1.368
GeO2 Germanium dioxide 3 Πu 196 152 -43 1.285
NaOH sodium hydroxide 3 Π 300 100 -200 2.999
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.549
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 111 -60 1.547
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.549
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 111 -60 1.547
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.358
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.359
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.358
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.359
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.663
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.663
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
C2H5 Ethyl radical 9 A' 528 435 -93 1.213
CH3 Methyl radical 2 A2" 606 412 -195 1.472
CH3 Methyl radical 2 A2" 606 412 -195 1.472
CH3 Methyl radical 2 A2" 606 412 -195 1.472
CH3 Methyl radical 2 A2" 606 412 -195 1.472
CH2OH Hydroxymethyl radical 8 A 482 712 230 0.677
CH2OH Hydroxymethyl radical 9 A 234 426 192 0.549
C3H3 Propargyl radical 7 B1 490 398 -92 1.232
C4H6 Methylenecyclopropane 17 B1 360 270 -90 1.332
OH- hydroxide anion 1 Σ 3738 3272 -466 1.142
BF3+ boron trifluoride cation 3 E' 1662 574 -1087 2.892
BF3+ boron trifluoride cation 4 E' 411 -1058 -1469 -0.388
C2Cl2 dichloroacetylene 4 Πg 333 180 -153 1.853
C2Cl2+ dichloroacetylene cation 5 Πu 233 168 -65 1.388
CuCl Copper monochloride 1 Σ 418 266 -152 1.570
MgF2 Magnesium fluoride 3 Πu 165 136 -29 1.214
FOOF Perfluoroperoxide 1 A 1210 957 -253 1.265
ZnCN Zinc monocyanide 3 Π 212 81 -131 2.606
BrF5 bromine pentafluoride 6 B2 281 222 -59 1.263
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.327
CaOH Calcium monohydroxide 2 Σ 353 607 254 0.582
CaOH Calcium monohydroxide 3 Π 609 376 -233 1.621
N2O3 Dinitrogen trioxide 9 A" 63 134 71 0.469
NO3 Nitrogen trioxide 3 E' 1492 1108 -385 1.347
NO3 Nitrogen trioxide 4 E' 360 119 -241 3.033
C4 Carbon tetramer 4 Πg 323 255 -68 1.267
Li2O dilithium oxide 3 Πu 112 43 -69 2.616
C3 carbon trimer 3 Πu 63 45 -18 1.404
C3 carbon trimer 3 Πu 63 47 -16 1.338
C3 carbon trimer 3 Πu 63 45 -18 1.404
C3 carbon trimer 3 Πu 63 47 -16 1.338
CuF Copper monofluoride 1 Σ 623 477 -146 1.306
SiH- silicon monohydride anion 1 Σ 2175 1736 -439 1.253
SiH- silicon monohydride anion 1 Σ 2175 1736 -439 1.253
SiH- silicon monohydride anion 1 Σ 2175 1736 -439 1.253
SiH- silicon monohydride anion 1 Σ 2175 1736 -439 1.253
ZnH2 Zinc hydride 3 Πu 633 473 -159 1.337
SF5Cl sulfur chloropentafluoride 5 B1 625 453 -172 1.381
SF5Cl sulfur chloropentafluoride 7 B2 505 311 -194 1.625
SF5Cl sulfur chloropentafluoride 11 E 397 244 -153 1.630
Cl3- trichloride anion 2 Σu 327 222 -105 1.476
Mg2 Magnesium diatomic 1 Σg 51 299 248 0.171
Mg2 Magnesium diatomic 1 Σg 51 299 248 0.171
Mg2 Magnesium diatomic 1 Σg 51 299 248 0.171
Mg2 Magnesium diatomic 1 Σg 51 299 248 0.171
GeH2 germylene 1 A1 1856 887 -969 2.092
GeH2 germylene 2 A1 916 1716 800 0.534
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524
H2POH Phosphinous acid 9 A" 375 251 -125 1.497