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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 HF/CEP-121G*
Calculated values were scaled by 0.9034.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 166 53 0.680
CH3OH Methyl alcohol 12 A" 200 311 111 0.643
CH3OH Methyl alcohol 12 A" 200 311 111 0.643
CH3OH Methyl alcohol 12 A" 200 311 111 0.643
CH3OH Methyl alcohol 12 A" 200 311 111 0.643
C2H6O2S Dimethyl sulfone 20 B1 262 203 -59 1.290
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 229 -47 1.205
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 229 -47 1.205
CH3COCl Acetyl Chloride 15 A" 166 137 -29 1.216
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 519 -113 1.217
C3F8 perfluoropropane 13 A2 276 221 -55 1.248
CH3COOCH3 methyl acetate 27 A" 110 70 -40 1.572
C6H4O2 parabenzoquinone 17 B2g 241 181 -60 1.334
C6H4O2 parabenzoquinone 30 B3u 109 86 -23 1.268
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.747
C5H12 Pentane 23 A2 131 99 -32 1.325
C4H8O Furan, tetrahydro- 17 A 286 235 -51 1.217
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 154 -39 1.255
C4H8O2 1,4-Dioxane 19 Au 288 237 -51 1.215
CH3NHCH3 Dimethylamine 24 A" 257 213 -44 1.209
C5H8 Cyclopentene 18 A' 254 144 -110 1.769
C2H3N3 1H-1,2,4-Triazole 18 A" 640 507 -133 1.263
C6H4 Benzyne 24 B2 472 244 -228 1.932
C4H6O2 2,3-Butanedione 9 Ag 614 512 -102 1.200
C4H6O2 2,3-Butanedione 21 Bg 240 115 -125 2.089
C4H2 Diacetylene 6 Πg 627 1228 601 0.510
C4H2 Diacetylene 7 Πg 482 708 226 0.681
C4H2 Diacetylene 8 Πu 630 925 295 0.681
NH2CN cyanamide 5 A' 408 691 283 0.590
HCNO fulminic acid 5 Π 224 543 319 0.412
C3H6O Oxetane 12 A2 986 805 -181 1.225
C2H3NO3 Oxamic acid 3 A' 2600 3456 856 0.752
C2H3NO3 Oxamic acid 15 A' 328 261 -67 1.258
C2H3NO3 Oxamic acid 17 A" 815 633 -182 1.288
C2H3NO3 Oxamic acid 18 A" 745 583 -162 1.278
C2H3NO3 Oxamic acid 20 A" 315 227 -88 1.388
C2H3NO3 Oxamic acid 21 A" 162 18 -144 9.168
C3O2 Carbon suboxide 7 Πu 61 148 87 0.411
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C6H10 1,5-Hexadiene 14 Ag 351 251 -100 1.399
C6H10 1,5-Hexadiene 29 Bg 264 160 -104 1.654
CH3SSCH3 Disulfide, dimethyl 13 A 117 89 -28 1.310
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 141 -29 1.206
CH2D2 methane-d2 6 B1 3013 2194 -819 1.373
CH2D2 methane-d2 8 B2 2234 2961 727 0.754
C2F2 difluoroacetylene 4 Πg 270 415 145 0.651
C4H6O Cyclobutanone 20 B1 63 8 -55 8.157
C4H6O Cyclobutanone 12 A2 1163 933 -230 1.246
C4H6O Cyclobutanone 13 A2 909 626 -283 1.452
C4N2 2-Butynedinitrile 3 Σg 692 566 -126 1.223
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.686
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.685
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.686
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.685
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 353 -103 1.291
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 353 -103 1.291
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 353 -103 1.291
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 353 -103 1.291
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 117 -54 1.458
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 119 -52 1.432
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 117 -54 1.458
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 119 -52 1.432
C2H5 Ethyl radical 9 A' 528 412 -116 1.282
C2H+ Ethynyl cation 3 Π 550 861 311 0.638
CH3 Methyl radical 2 A2" 606 265 -342 2.291
CH3 Methyl radical 2 A2" 606 265 -342 2.291
CH3 Methyl radical 2 A2" 606 265 -342 2.291
CH3 Methyl radical 2 A2" 606 265 -342 2.291
C4H9N Cyclobutylamine 21 A' 174 142 -32 1.226
CH2OH Hydroxymethyl radical 8 A 482 787 305 0.612
CH2OH Hydroxymethyl radical 9 A 234 377 143 0.621
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 844 -292 1.345
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 128 -136 2.060
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 90 -268 3.993
C2Cl2+ dichloroacetylene cation 5 Πu 233 188 -45 1.237
MgF2 Magnesium fluoride 3 Πu 165 129 -36 1.280
FOOF Perfluoroperoxide 2 A 630 1047 417 0.602
FOOF Perfluoroperoxide 5 B 614 1033 419 0.594
PCl5 Phosphorus pentachloride 2 A1' 370 277 -93 1.334
N2O4 Dinitrogen tetroxide 3 Ag 265 411 146 0.644
N2O4 Dinitrogen tetroxide 4 Au 82 49 -33 1.665
N2O3 Dinitrogen trioxide 6 A' 241 405 164 0.595
N2O3 Dinitrogen trioxide 7 A' 205 328 123 0.626
N2O3 Dinitrogen trioxide 8 A" 414 607 193 0.682
NS Mononitrogen monosulfide 1 Σ 1219 795 -424 1.533
SiN Silicon nitride 1 Σ 1151 780 -372 1.477
C3 carbon trimer 3 Πu 63 274 211 0.231
C3 carbon trimer 3 Πu 63 274 211 0.231
C3 carbon trimer 3 Πu 63 274 211 0.231
C3 carbon trimer 3 Πu 63 274 211 0.231
MgOH magnesium hydroxide 3 Π 188 148 -40 1.267
PS phosphorus sulfide 1 Σ 739 477 -262 1.549
CP Carbon monophosphide 1 Σ 1240 879 -361 1.411
S3- Sulfur trimer anion 3 B2 594 469 -125 1.267
HOClO Chlorous acid 3 A 978 759 -219 1.288
SiH- silicon monohydride anion 1 Σ 2175 1707 -468 1.274
SiH- silicon monohydride anion 1 Σ 2175 1707 -468 1.274
SiH- silicon monohydride anion 1 Σ 2175 1707 -468 1.274
SiH- silicon monohydride anion 1 Σ 2175 1707 -468 1.274
SF5Cl sulfur chloropentafluoride 5 B1 625 480 -145 1.301
SF5Cl sulfur chloropentafluoride 7 B2 505 332 -173 1.520
SF5Cl sulfur chloropentafluoride 11 E 397 258 -139 1.541
PN+ phosphorus nitride cation 1 Σ 1200 610 -590 1.968
AlO Aluminum monoxide 1 Σ 979 693 -286 1.413
ClOO chloroperoxy radical 1 A' 1443 1084 -359 1.331
ClOO chloroperoxy radical 2 A' 414 628 214 0.659
ClOO chloroperoxy radical 3 A' 201 395 193 0.510
AlN Aluminum nitride 1 Σ 747 621 -125 1.202
F3- trifluoride anion 2 Σu 550 -434 -984 -1.268
H2POH Phosphinous acid 9 A" 375 252 -123 1.487
Cl3- trichloride anion 2 Σu 327 -94 -421 -3.468
ClS2 Sulfur chloride 1 A' 662 536 -126 1.235
NNS Nitrogen sulfide 2 Σ 752 522 -230 1.440
Mg2 Magnesium diatomic 1 Σg 51 2 -49 20.736
ONONO Nitrosyl nitrite 9 B2 380 711 331 0.535