return to home page

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
CH3OH Methyl alcohol 12 A" 200 329 129 0.608
CH3OH Methyl alcohol 12 A" 200 326 126 0.613
CH3OH Methyl alcohol 12 A" 200 329 129 0.608
CH3OH Methyl alcohol 12 A" 200 326 126 0.613
CH3COOH Acetic acid 18 A" 93 70 -23 1.338
C2H6O2S Dimethyl sulfone 13 A2 326 271 -55 1.204
C2H6O2S Dimethyl sulfone 20 B1 262 202 -60 1.296
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
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
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
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 16 A 137 282 145 0.485
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.210
Zn(CH3)2 dimethyl zinc 11 E' 134 103 -31 1.298
C6H10 1,5-Hexadiene 14 Ag 351 266 -85 1.318
C6H10 1,5-Hexadiene 29 Bg 264 219 -45 1.205
COBr2 Carbonic dibromide 4 B1 757 526 -231 1.440
COBr2 Carbonic dibromide 6 B2 512 348 -164 1.472
CH3SSCH3 Disulfide, dimethyl 13 A 117 71 -46 1.638
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
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 134 -36 1.266
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
CuO Copper Monoxide 1 Σ 640 947 307 0.676
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
CH2OH Hydroxymethyl radical 9 A 234 430 196 0.545
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 872 -264 1.303
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
C4H6 Methylenecyclopropane 17 B1 360 290 -70 1.242
HClO4 perchloric acid 12 A" 191 138 -53 1.381
BF3+ boron trifluoride cation 3 E' 1662 1238 -424 1.342
BF3+ boron trifluoride cation 4 E' 411 259 -152 1.586
GaF3 Gallium trifluoride 4 E' 192 81 -111 2.383
ZnCN Zinc monocyanide 3 Π 212 93 -119 2.281
AsF5 Arsenic pentafluoride 7 E' 123 98 -25 1.252
BrF5 bromine pentafluoride 6 B2 281 234 -47 1.200
CaF2 Calcium difluoride 2 A1 120 99 -21 1.217
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
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.223
PCl5 Phosphorus pentachloride 2 A1' 370 290 -80 1.276
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.212
N2O3 Dinitrogen trioxide 9 A" 63 153 90 0.411
Li2O dilithium oxide 3 Πu 112 163 52 0.683
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
ClOO chloroperoxy radical 3 A' 201 326 124 0.618
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
H3O+ hydronium 2 A1 954 728 -227 1.311
ZnH2 Zinc hydride 3 Πu 633 349 -284 1.813
H2POH Phosphinous acid 9 A" 375 253 -123 1.486
B2H6 Diborane 14 B2u 368 265 -103 1.388
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
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