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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 CCSD(T)/6-31G*
Calculated values were scaled by 0.9621.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 334 134 0.598
CH3OH Methyl alcohol 12 A" 200 335 135 0.596
CH3OH Methyl alcohol 12 A" 200 334 134 0.598
CH3OH Methyl alcohol 12 A" 200 335 135 0.596
C6H6 Benzene 8 B2g 703 515 -188 1.366
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 308 94 0.695
C2H2 Acetylene 4 Πg 612 319 -293 1.919
CH3CCH propyne 9 E 633 482 -151 1.312
CH3CCH propyne 10 E 328 213 -115 1.542
CBr2F2 Methane, dibromodifluoro- 3 A1 140 321 181 0.436
C6H5CN phenyl cyanide 19 B1 688 538 -150 1.278
C6H4O2 parabenzoquinone 16 B2g 794 650 -144 1.222
C6H4O2 parabenzoquinone 17 B2g 241 178 -63 1.352
C6H4O2 parabenzoquinone 30 B3u 109 88 -21 1.234
C3H2N2 Malononitrile 6 A1 167 133 -34 1.252
CH2NN diazomethane 6 B1 406 317 -89 1.282
NH2CN cyanamide 5 A' 408 678 270 0.602
NH2CN cyanamide 9 A" 435 362 -73 1.203
C4H2 Diacetylene 7 Πg 482 105 -377 4.597
C4H2 Diacetylene 8 Πu 630 424 -206 1.486
COBr2 Carbonic dibromide 4 B1 757 489 -268 1.547
COBr2 Carbonic dibromide 6 B2 512 327 -185 1.564
CH2D2 methane-d2 6 B1 3013 2263 -750 1.331
CH2D2 methane-d2 8 B2 2234 3055 821 0.731
C2F2 difluoroacetylene 4 Πg 270 114 -156 2.362
HCCCN Cyanoacetylene 6 Π 499 398 -101 1.254
GeO2 Germanium dioxide 3 Πu 196 145 -51 1.352
NaOH sodium hydroxide 3 Π 300 119 -181 2.527
CuO Copper Monoxide 1 Σ 640 6247 5607 0.102
C2H5 Ethyl radical 9 A' 528 438 -90 1.206
C2H Ethynyl radical 3 Π 372 296 -76 1.256
CH3 Methyl radical 2 A2" 606 416 -191 1.459
CH3 Methyl radical 2 A2" 606 416 -191 1.459
CH3 Methyl radical 2 A2" 606 416 -191 1.459
CH3 Methyl radical 2 A2" 606 416 -191 1.459
CH2 Methylene 2 A1 963 1404 441 0.686
CH2OH Hydroxymethyl radical 8 A 482 715 233 0.674
CH2OH Hydroxymethyl radical 9 A 234 435 201 0.538
C2H3+ vinyl cation 2 A1 2217 2931 714 0.756
HCCF Fluoroacetylene 5 Π 367 287 -80 1.279
C3H3 Propargyl radical 7 B1 490 396 -94 1.237
OH- hydroxide anion 1 Σ 3738 3265 -474 1.145
C2Cl2 dichloroacetylene 4 Πg 333 80 -253 4.187
HClO4 perchloric acid 12 A" 191 158 -33 1.208
HClO4 perchloric acid 12 A" 191 158 -33 1.208
H2O2 Hydrogen peroxide 4 A 371 309 -62 1.200
MgF2 Magnesium fluoride 3 Πu 165 137 -28 1.206
AsH3+ Arsine cation 2 A1 452 650 198 0.696
ZnCN Zinc monocyanide 3 Π 212 61 -151 3.482
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.441
Li2O dilithium oxide 3 Πu 112 49 -62 2.255
CaOH Calcium monohydroxide 2 Σ 353 613 260 0.576
CaOH Calcium monohydroxide 3 Π 609 378 -231 1.610
C4 Carbon tetramer 4 Πg 323 235 -88 1.374
KrF2 Krypton difluoride 1 Σg 449 369 -80 1.217
SiH- silicon monohydride anion 1 Σ 2175 1744 -431 1.247
SF5Cl sulfur chloropentafluoride 5 B1 625 450 -175 1.387
SF5Cl sulfur chloropentafluoride 7 B2 505 308 -197 1.639
SF5Cl sulfur chloropentafluoride 11 E 397 241 -156 1.646
ZnH2 Zinc hydride 3 Πu 633 477 -156 1.327
PO Phosphorus monoxide 1 Σ 1233 1020 -213 1.209
ClOO chloroperoxy radical 2 A' 414 339 -75 1.220
ClOO chloroperoxy radical 3 A' 201 119 -83 1.698
Cl3- trichloride anion 2 Σu 327 261 -66 1.255
GeH2 germylene 1 A1 1856 892 -964 2.080
GeH2 germylene 2 A1 916 1725 809 0.531
H2OH2O water dimer 11 A" 108 154 46 0.700
H2OH2O water dimer 11 A" 108 154 46 0.700
H2POH Phosphinous acid 9 A" 375 250 -126 1.503
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.318
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.318
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.318
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.318
ZnCH3 Zinc monomethyl 6 E 315 603 288 0.523