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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 LSDA/6-31G(2df,p)
Calculated values were scaled by 0.984.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 185 72 0.612
CH3COOH Acetic acid 18 A" 93 70 -23 1.338
CH3OH Methyl alcohol 12 A" 200 329 129 0.608
CH3OH Methyl alcohol 12 A" 200 326 126 0.613
C2H6O2S Dimethyl sulfone 13 A2 326 271 -55 1.204
C2H6O2S Dimethyl sulfone 20 B1 262 202 -60 1.296
CH3OH Methyl alcohol 12 A" 200 329 129 0.608
CH3OH Methyl alcohol 12 A" 200 326 126 0.613
CH3COCl Acetyl Chloride 15 A" 166 134 -32 1.241
CBr2F2 Methane, dibromodifluoro- 3 A1 140 345 205 0.405
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.523
C3F8 perfluoropropane 13 A2 276 201 -75 1.372
C3H6O 2-Propen-1-ol 22 A 377 301 -76 1.252
C3H6O 2-Propen-1-ol 24 A 188 118 -70 1.590
CH3OCHO methyl formate 18 A" 130 90 -40 1.449
C3H2N2 Malononitrile 6 A1 167 139 -28 1.203
C5H8 Cyclopentene 18 A' 254 160 -94 1.586
C4H4N2 Pyridazine 13 A2 421 338 -83 1.244
C4H6O2 2,3-Butanedione 21 Bg 240 51 -189 4.745
C6H4 Benzyne 24 B2 472 382 -90 1.236
C5H12 Propane, 2,2-dimethyl- 12 T1 203 318 115 0.638
C2H2N4 sym-tetrazine 5 Au 335 268 -67 1.249
C2H2N4 sym-tetrazine 18 B3u 254 -60 -314 -4.215
C4H6O2 2,3-Butanedione 9 Ag 614 509 -105 1.206
C4H6O2 2,3-Butanedione 13 Au 1111 868 -243 1.280
C4H6O2 2,3-Butanedione 16 Au 48 -33 -81 -1.437
C2H3NO3 Oxamic acid 3 A' 2600 3433 833 0.757
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 16 A" 984 809 -175 1.217
C2H3NO3 Oxamic acid 21 A" 162 87 -75 1.853
C3O2 Carbon suboxide 7 Πu 61 97 36 0.627
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.210
C6H10 1,5-Hexadiene 29 Bg 264 219 -45 1.205
Zn(CH3)2 dimethyl zinc 11 E' 134 103 -31 1.298
C5H8 1,4-Pentadiene 16 A 137 282 145 0.485
COBr2 Carbonic dibromide 4 B1 757 526 -231 1.440
COBr2 Carbonic dibromide 6 B2 512 348 -164 1.472
C6H10 1,5-Hexadiene 14 Ag 351 266 -85 1.318
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 179 -48 1.269
CH2D2 methane-d2 6 B1 3013 2279 -734 1.322
CH2D2 methane-d2 8 B2 2234 3078 844 0.726
CH2D2 methane-d2 9 B2 1234 1026 -208 1.202
CH3SSCH3 Disulfide, dimethyl 13 A 117 71 -46 1.638
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 134 -36 1.266
CuO Copper Monoxide 1 Σ 640 947 307 0.676
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 345 -111 1.323
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.325
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 345 -111 1.323
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.325
CH3OO methylperoxy radical 12 A" 170 121 -49 1.407
CH3 Methyl radical 2 A2" 606 487 -119 1.245
CH3 Methyl radical 2 A2" 606 485 -122 1.251
CH3 Methyl radical 2 A2" 606 487 -119 1.245
CH3 Methyl radical 2 A2" 606 485 -122 1.251
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 165 -99 1.599
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 109 -249 3.291
CH2OH Hydroxymethyl radical 9 A 234 430 196 0.545
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 872 -264 1.303
HClO4 perchloric acid 12 A" 191 138 -53 1.381
C4H6 Methylenecyclopropane 17 B1 360 290 -70 1.242
BF3+ boron trifluoride cation 3 E' 1662 1238 -424 1.342
BF3+ boron trifluoride cation 4 E' 411 259 -152 1.586
AsF5 Arsenic pentafluoride 7 E' 123 98 -25 1.252
GaF3 Gallium trifluoride 4 E' 192 81 -111 2.383
CaF2 Calcium difluoride 2 A1 120 99 -21 1.217
ZnCN Zinc monocyanide 3 Π 212 93 -119 2.281
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.223
BrF5 bromine pentafluoride 6 B2 281 234 -47 1.200
PCl5 Phosphorus pentachloride 2 A1' 370 290 -80 1.276
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.212
Li2O dilithium oxide 3 Πu 112 163 52 0.683
N2O3 Dinitrogen trioxide 9 A" 63 153 90 0.411
C3 carbon trimer 3 Πu 63 109 45 0.582
C3 carbon trimer 3 Πu 63 108 45 0.585
C3 carbon trimer 3 Πu 63 109 45 0.582
C3 carbon trimer 3 Πu 63 108 45 0.585
SF5Cl sulfur chloropentafluoride 5 B1 625 476 -149 1.312
SF5Cl sulfur chloropentafluoride 7 B2 505 317 -188 1.592
SF5Cl sulfur chloropentafluoride 11 E 397 251 -146 1.580
B2Cl4 Diboron tetrachloride 9 E 104 80 -24 1.294
SiH- silicon monohydride anion 1 Σ 2175 1788 -387 1.217
SiH- silicon monohydride anion 1 Σ 2175 1788 -387 1.217
SiH- silicon monohydride anion 1 Σ 2175 1788 -387 1.217
SiH- silicon monohydride anion 1 Σ 2175 1788 -387 1.217
B2H6 Diborane 14 B2u 368 265 -103 1.388
H3O+ hydronium 2 A1 954 728 -227 1.311
ZnH2 Zinc hydride 3 Πu 633 349 -284 1.813
ClOO chloroperoxy radical 3 A' 201 326 124 0.618
GeH2 germylene 1 A1 1856 898 -958 2.067
GeH2 germylene 2 A1 916 1890 974 0.485
H2OH2O water dimer 6 A' 311 540 229 0.576
H2OH2O water dimer 7 A' 143 300 157 0.476
H2OH2O water dimer 10 A" 523 768 245 0.681
H2OH2O water dimer 11 A" 108 185 77 0.584
H2OH2O water dimer 12 A" 88 -199 -287 -0.442
H2POH Phosphinous acid 9 A" 375 253 -123 1.486
Mg2 Magnesium diatomic 1 Σg 51 124 73 0.412
Mg2 Magnesium diatomic 1 Σg 51 124 73 0.412
Mg2 Magnesium diatomic 1 Σg 51 124 73 0.412
Mg2 Magnesium diatomic 1 Σg 51 124 73 0.412
ZnCH3 Zinc monomethyl 6 E 315 563 248 0.559