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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(T)/6-31G*
Calculated values were scaled by 0.9593.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 333 133 0.600
CH3OH Methyl alcohol 12 A" 200 334 134 0.598
CH3OH Methyl alcohol 12 A" 200 333 133 0.600
CH3OH Methyl alcohol 12 A" 200 334 134 0.598
C2H2 Acetylene 4 Πg 612 314 -298 1.951
CH3CCH propyne 9 E 633 480 -153 1.320
CH3CCH propyne 10 E 328 210 -118 1.559
HCN+ hydrogen cyanide cation 3 Π 760 1877 1117 0.405
CBr2F2 Methane, dibromodifluoro- 3 A1 140 320 180 0.438
C6H4O2 parabenzoquinone 30 B3u 109 87 -21 1.245
C6H4O2 parabenzoquinone 16 B2g 794 648 -146 1.225
C6H4O2 parabenzoquinone 17 B2g 241 178 -63 1.353
C3H2N2 Malononitrile 6 A1 167 133 -34 1.256
CH3COOCH3 methyl acetate 27 A" 110 57 -53 1.937
C6H5CN phenyl cyanide 19 B1 688 538 -150 1.279
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.203
NH2CN cyanamide 5 A' 408 675 267 0.604
NH2CN cyanamide 9 A" 435 360 -75 1.208
C6H5F Fluorobenzene 18 B1 685 511 -174 1.341
CH2NN diazomethane 6 B1 406 318 -88 1.278
CH2D2 methane-d2 6 B1 3013 2256 -757 1.336
CH2D2 methane-d2 8 B2 2234 3045 811 0.734
NaOH sodium hydroxide 3 Π 300 149 -151 2.018
COBr2 Carbonic dibromide 4 B1 757 487 -270 1.555
COBr2 Carbonic dibromide 6 B2 512 325 -187 1.575
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 217 73 0.662
GeO2 Germanium dioxide 3 Πu 196 143 -53 1.369
CuO Copper Monoxide 1 Σ 640 7239 6599 0.088
C2F2 difluoroacetylene 4 Πg 270 101 -169 2.661
HCCCN Cyanoacetylene 5 Π 663 552 -111 1.202
HCCCN Cyanoacetylene 6 Π 499 396 -103 1.260
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 112 -59 1.526
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 112 -59 1.526
C2H5 Ethyl radical 9 A' 528 436 -92 1.210
CH2OH Hydroxymethyl radical 8 A 482 714 232 0.675
CH2OH Hydroxymethyl radical 9 A 234 433 199 0.540
HCCF Fluoroacetylene 5 Π 367 283 -84 1.298
CH3 Methyl radical 2 A2" 606 414 -192 1.464
CH3 Methyl radical 2 A2" 606 414 -192 1.464
CH3 Methyl radical 2 A2" 606 414 -192 1.464
CH3 Methyl radical 2 A2" 606 414 -192 1.464
OH- hydroxide anion 1 Σ 3738 3254 -484 1.149
C2H Ethynyl radical 3 Π 372 307 -64 1.209
C2Cl2+ dichloroacetylene cation 4 Πg 318 260 -58 1.225
CuCl Copper monochloride 1 Σ 418 837 420 0.499
C2Cl2+ dichloroacetylene cation 5 Πu 233 163 -70 1.427
BF3+ boron trifluoride cation 3 E' 1662 12106 10445 0.137
BF3+ boron trifluoride cation 4 E' 411 2272 1861 0.181
H2O2 Hydrogen peroxide 4 A 371 308 -63 1.203
AsH3+ Arsine cation 2 A1 452 647 195 0.698
HClO4 perchloric acid 12 A" 191 154 -37 1.236
HClO4 perchloric acid 12 A" 191 154 -37 1.236
MgF2 Magnesium fluoride 3 Πu 165 136 -29 1.211
BrF5 bromine pentafluoride 6 B2 281 216 -65 1.303
FO Oxygen monofluoride 1 Σ 1053 869 -184 1.211
ZnCN Zinc monocyanide 3 Π 212 61 -151 3.497
CuF Copper monofluoride 1 Σ 623 1197 574 0.520
C4 Carbon tetramer 4 Πg 323 198 -125 1.635
Li2O dilithium oxide 3 Πu 112 54 -57 2.060
CuH Copper monohydride 1 Σ 1941 3181 1240 0.610
CuH Copper monohydride 1 Σ 1941 3181 1240 0.610
CuH Copper monohydride 1 Σ 1941 3181 1240 0.610
CuH Copper monohydride 1 Σ 1941 3181 1240 0.610
CaOH Calcium monohydroxide 2 Σ 353 610 257 0.578
CaOH Calcium monohydroxide 3 Π 609 374 -235 1.629
N2O3 Dinitrogen trioxide 9 A" 63 138 75 0.457
SF5Cl sulfur chloropentafluoride 5 B1 625 448 -177 1.394
SF5Cl sulfur chloropentafluoride 7 B2 505 307 -198 1.646
SF5Cl sulfur chloropentafluoride 11 E 397 240 -157 1.653
ZnH2 Zinc hydride 3 Πu 633 474 -159 1.334
SiH- silicon monohydride anion 1 Σ 2175 1738 -437 1.252
SiH- silicon monohydride anion 1 Σ 2175 1737 -438 1.252
SiH- silicon monohydride anion 1 Σ 2175 1738 -437 1.252
SiH- silicon monohydride anion 1 Σ 2175 1737 -438 1.252
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.323
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.323
GeH2 germylene 1 A1 1856 889 -967 2.087
GeH2 germylene 2 A1 916 1719 803 0.533
Cl3- trichloride anion 2 Σu 327 257 -70 1.270
H2POH Phosphinous acid 9 A" 375 249 -126 1.508
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524