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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 B2PLYP/6-31G*
Calculated values were scaled by 0.9492.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 171 58 0.661
CH3OH Methyl alcohol 12 A" 200 330 130 0.605
CH3OH Methyl alcohol 12 A" 200 330 130 0.605
CH3COOH Acetic acid 18 A" 93 77 -16 1.203
CH3COCH3 Acetone 12 A2 77 45 -32 1.718
C2H6O2S Dimethyl sulfone 13 A2 326 269 -57 1.210
C2H6O2S Dimethyl sulfone 20 B1 262 208 -54 1.259
C2H4+ Ethylene cation 4 Au 84 -324 -408 -0.259
CHONH2 formamide 12 A" 289 -73 -362 -3.928
CH3COCl Acetyl Chloride 15 A" 166 132 -34 1.255
C3F8 perfluoropropane 13 A2 276 210 -66 1.315
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 59 -16 1.268
C2F6 hexafluoroethane 4 A1u 68 50 -18 1.356
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 520 -112 1.214
CH3COOCH3 methyl acetate 27 A" 110 54 -56 2.022
CH3COCH2CH3 2-Butanone 33 A" 87 18 -69 4.909
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.699
C3H2N2 Malononitrile 6 A1 167 137 -30 1.215
C5H12 Pentane 23 A2 131 107 -24 1.224
C4H8S Thiophene, tetrahydro- 27 B 1125 2950 1825 0.381
C4H8S Thiophene, tetrahydro- 28 B 1061 2929 1868 0.362
C4H8S Thiophene, tetrahydro- 29 B 1037 1466 429 0.708
C4H8S Thiophene, tetrahydro- 32 B 516 871 355 0.592
C4H8S Thiophene, tetrahydro- 3 A 2922 1327 -1595 2.201
C4H8S Thiophene, tetrahydro- 4 A 2862 1279 -1583 2.238
C4H8S Thiophene, tetrahydro- 5 A 1464 1208 -256 1.212
C4H8S Thiophene, tetrahydro- 6 A 1441 1015 -426 1.420
C4H8S Thiophene, tetrahydro- 7 A 1321 864 -457 1.529
C4H8S Thiophene, tetrahydro- 8 A 1276 666 -610 1.917
C4H8S Thiophene, tetrahydro- 9 A 1213 280 -933 4.338
C4H8S Thiophene, tetrahydro- 26 B 1196 3007 1811 0.398
C4H8O Furan, tetrahydro- 33 B 137 39 -98 3.500
C5H8 Cyclopentene 18 A' 254 148 -106 1.715
C2H4O3 trioxolane124 21 B 193 158 -35 1.220
C2H3N3 1H-1,2,4-Triazole 18 A" 640 513 -127 1.247
CH2NN diazomethane 6 B1 406 337 -69 1.203
NH2CN cyanamide 5 A' 408 612 204 0.667
C4H2 Diacetylene 8 Πu 630 518 -112 1.215
C4H6O2 2,3-Butanedione 9 Ag 614 503 -111 1.220
C4H6O2 2,3-Butanedione 21 Bg 240 112 -128 2.150
C5H12 Propane, 2,2-dimethyl- 12 T1 203 290 87 0.700
HCNO fulminic acid 5 Π 224 -177 -401 -1.269
C2H3NO3 Oxamic acid 3 A' 2600 3438 838 0.756
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.267
C2H3NO3 Oxamic acid 16 A" 984 773 -211 1.273
C2H3NO3 Oxamic acid 17 A" 815 658 -157 1.239
C2H3NO3 Oxamic acid 18 A" 745 611 -134 1.220
C2H3NO3 Oxamic acid 21 A" 162 60 -102 2.703
C3O2 Carbon suboxide 7 Πu 61 115 54 0.528
CH3CCCH3 2-Butyne 16 E" 371 301 -70 1.232
C3H6O Oxetane 12 A2 986 815 -171 1.209
C3H6O Oxetane 18 B1 90 -7 -97 -12.370
C3H6O Oxetane 23 B2 1228 1002 -226 1.226
Zn(CH3)2 dimethyl zinc 2 A1' 1157 2913 1756 0.397
Zn(CH3)2 dimethyl zinc 3 A1' 503 1246 743 0.404
Zn(CH3)2 dimethyl zinc 11 E' 134 2979 2845 0.045
C5H8 1,4-Pentadiene 16 A 137 288 151 0.476
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.203
C5H8 1,4-Pentadiene 31 B 721 586 -135 1.230
C5H8 1,4-Pentadiene 33 B 331 97 -234 3.400
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.233
C2F2 difluoroacetylene 4 Πg 270 183 -87 1.473
C6H10 2-Hexyne 25 A' 115 94 -21 1.217
C6H10 2-Hexyne 38 A" 392 316 -76 1.242
C5H8O Methyl cyclopropyl ketone 7 A' 1458 1185 -273 1.230
C5H8O Methyl cyclopropyl ketone 8 A' 1441 1158 -283 1.244
C5H8O Methyl cyclopropyl ketone 9 A' 1386 1036 -350 1.338
C5H8O Methyl cyclopropyl ketone 10 A' 1352 943 -409 1.433
C5H8O Methyl cyclopropyl ketone 11 A' 1201 890 -311 1.349
C5H8O Methyl cyclopropyl ketone 12 A' 1170 727 -443 1.610
C5H8O Methyl cyclopropyl ketone 13 A' 1096 357 -739 3.067
C5H8O Methyl cyclopropyl ketone 30 A" 1028 3026 1998 0.340
C5H8O Methyl cyclopropyl ketone 31 A" 865 1422 557 0.608
C5H8O Methyl cyclopropyl ketone 32 A" 822 1177 355 0.699
C5H8O Methyl cyclopropyl ketone 33 A" 601 1020 419 0.589
C5H8O Methyl cyclopropyl ketone 34 A" 265 578 313 0.458
C5H8O Methyl cyclopropyl ketone 4 A' 2970 1690 -1280 1.757
C5H8O Methyl cyclopropyl ketone 5 A' 2929 1438 -1491 2.036
C5H8O Methyl cyclopropyl ketone 6 A' 1725 1376 -349 1.254
NaOH sodium hydroxide 3 Π 300 -119 -419 -2.525
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 141 -29 1.209
C2H+ Ethynyl cation 3 Π 550 817 267 0.673
CH3 Methyl radical 2 A2" 606 416 -191 1.460
CH3OO methylperoxy radical 12 A" 170 134 -36 1.269
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 97 -261 3.706
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 141 -123 1.868
CH2OH Hydroxymethyl radical 8 A 482 690 208 0.699
CH2OH Hydroxymethyl radical 9 A 234 435 201 0.538
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 862 -274 1.317
OH- hydroxide anion 1 Σ 3738 3299 -439 1.133
C4H6 Methylenecyclopropane 17 B1 360 274 -86 1.315
C6H6 2,4-Hexadiyne 2 A1' 2265 2917 652 0.777
C6H6 2,4-Hexadiyne 3 A1' 1381 2232 851 0.619
C6H6 2,4-Hexadiyne 5 A1' 554 1238 684 0.448
C2Cl2+ dichloroacetylene cation 5 Πu 233 171 -62 1.363
C2Cl2 dichloroacetylene 4 Πg 333 213 -120 1.565
HClO4 perchloric acid 12 A" 191 151 -40 1.261
ClFO3 Perchloryl fluoride 6 E 405 330 -75 1.229
SF4 Sulfur tetrafluoride 4 A1 228 184 -44 1.242
H3BO3 Boric acid 3 A' 866 3629 2763 0.239
AsF5 Arsenic pentafluoride 6 E' 372 823 451 0.452
AsF5 Arsenic pentafluoride 7 E' 123 333 210 0.370
ZnCN Zinc monocyanide 3 Π 212 64 -148 3.291
N2O4 Dinitrogen tetroxide 9 B2u 265 208 -57 1.271
PCl5 Phosphorus pentachloride 2 A1' 370 265 -105 1.396
BrF5 bromine pentafluoride 6 B2 281 206 -75 1.361
S8 Octasulfur 5 E1 471 184 -287 2.564
S8 Octasulfur 7 E2 475 236 -239 2.014
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.588
CaOH Calcium monohydroxide 3 Π 609 343 -266 1.775
N2O3 Dinitrogen trioxide 9 A" 63 148 85 0.425
C3 carbon trimer 3 Πu 63 170 106 0.374
C5H5- cylopentadienyl anion 6 E1' 1455 3009 1554 0.483
C5H5- cylopentadienyl anion 7 E1' 1003 1433 430 0.700
C5H5- cylopentadienyl anion 11 E2' 1020 2985 1965 0.342
C5H5- cylopentadienyl anion 12 E2' 854 1362 508 0.627
Cu2 Copper dimer 1 Σg 265 386 122 0.685
B2Cl4 Diboron tetrachloride 9 E 104 -101 -205 -1.026
B2Cl4 Diboron tetrachloride 1 A1 1122 1792 670 0.626
B2Cl4 Diboron tetrachloride 8 E 512 249 -263 2.057
ZnH2 Zinc hydride 3 Πu 633 496 -137 1.276
SiH- silicon monohydride anion 1 Σ 2175 1756 -419 1.239
FO2 Dioxygen monofluoride 2 A' 579 1296 717 0.447
FO2 Dioxygen monofluoride 3 A' 376 556 180 0.676
SF5Cl sulfur chloropentafluoride 5 B1 625 441 -184 1.417
SF5Cl sulfur chloropentafluoride 7 B2 505 299 -206 1.690
SF5Cl sulfur chloropentafluoride 11 E 397 234 -163 1.693
H2OH2O water dimer 7 A' 143 216 73 0.661
H2OH2O water dimer 11 A" 108 158 50 0.683
H2OH2O water dimer 12 A" 88 25 -63 3.523
H2OH2O water dimer 7 A' 143 216 73 0.661
H2OH2O water dimer 11 A" 108 158 50 0.683
H2OH2O water dimer 12 A" 88 25 -63 3.523
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.530
Mg2 Magnesium diatomic 1 Σg 51 26 -25 1.957
Al2 Aluminum diatomic 1 Σg 286 208 -78 1.376