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 MP2FC/6-311G*
Calculated values were scaled by 0.9503.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.695
CH3CONH2 Acetamide 20 A 259 380 121 0.681
CH3COOH Acetic acid 18 A" 93 71 -22 1.315
CH3OH Methyl alcohol 12 A" 200 349 149 0.573
C2H6O2S Dimethyl sulfone 20 B1 262 213 -49 1.231
C6H6 Benzene 8 B2g 703 379 -324 1.856
C6H6 Benzene 7 B2g 995 827 -168 1.203
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 328 114 0.652
C2H2 Acetylene 4 Πg 612 377 -235 1.623
CH3NH2 methyl amine 14 A" 1195 949 -246 1.260
HCN+ hydrogen cyanide cation 2 Σ 1800 2759 959 0.652
HCN+ hydrogen cyanide cation 1 Σ 3050 3690 640 0.827
CH3CCH propyne 9 E 633 508 -125 1.246
CH3CCH propyne 10 E 328 227 -101 1.447
CBr2F2 Methane, dibromodifluoro- 3 A1 140 330 190 0.425
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.324
CH3COOCH3 methyl acetate 27 A" 110 45 -65 2.438
C6H5CN phenyl cyanide 20 B1 542 444 -98 1.220
C6H5CN phenyl cyanide 19 B1 688 527 -161 1.305
C6H5CHO benzaldehyde 32 A" 688 411 -277 1.673
C6H4O2 parabenzoquinone 17 B2g 241 159 -82 1.511
C6H4O2 parabenzoquinone 30 B3u 109 83 -26 1.311
CHCCH2CH3 1-Butyne 22 A" 630 524 -106 1.203
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.708
C3H6O 2-Propen-1-ol 21 A 554 430 -124 1.290
C6H5Cl chlorobenzene 19 B1 467 369 -98 1.265
C6H5Cl chlorobenzene 18 B1 685 422 -263 1.624
C5H12 Pentane 23 A2 131 96 -35 1.360
C3H2N2 Malononitrile 6 A1 167 137 -30 1.223
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 151 -42 1.280
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.202
C5H8 Cyclopentene 18 A' 254 178 -76 1.425
C5H8 Cyclopentene 29 A" 1082 898 -184 1.205
C3H3NO Isoxazole 14 A" 1033 809 -224 1.277
C2H3N3 1H-1,2,4-Triazole 14 A" 990 816 -174 1.214
C4H4N2 Pyridazine 13 A2 421 334 -87 1.259
NH2CN cyanamide 5 A' 408 673 265 0.606
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.018
C4H6O2 2,3-Butanedione 9 Ag 614 507 -107 1.210
C6H5F Fluorobenzene 15 B1 997 824 -173 1.210
C6H5F Fluorobenzene 18 B1 685 507 -178 1.352
CH3CCCH3 2-Butyne 16 E" 371 170 -201 2.184
C3O2 Carbon suboxide 7 Πu 61 36 -25 1.689
C6H4F2 1,4-difluorobenzene 16 B2g 692 551 -141 1.256
C5H8 1,4-Pentadiene 31 B 721 576 -145 1.251
C5H8 1,4-Pentadiene 33 B 331 93 -238 3.542
C5H8 1,4-Pentadiene 17 A 102 82 -20 1.238
C5H8 1,4-Pentadiene 16 A 137 293 156 0.468
C6H10 1,5-Hexadiene 29 Bg 264 159 -105 1.665
C6H10 1,5-Hexadiene 14 Ag 351 262 -89 1.338
C6H10 1,5-Hexadiene 20 Au 649 541 -108 1.200
COBr2 Carbonic dibromide 6 B2 512 336 -176 1.522
COBr2 Carbonic dibromide 4 B1 757 498 -259 1.521
CH3SSCH3 Disulfide, dimethyl 13 A 117 97 -20 1.204
C6H8 1,4-Cyclohexadiene 23 B2g 403 319 -84 1.263
C6H8 1,4-Cyclohexadiene 19 B1u 108 59 -49 1.826
CO+ carbon monoxide cation 1 Σ 2214 2739 525 0.808
C3H6O2 1,3-Dioxolane 5 A 1480 2910 1430 0.509
C3H6O2 1,3-Dioxolane 4 A 1509 2941 1432 0.513
C3H6O2 1,3-Dioxolane 6 A 1361 2857 1496 0.476
C3H6O2 1,3-Dioxolane 13 A 658 1239 581 0.531
C6H10 2-Hexyne 25 A' 115 88 -27 1.300
C6H10 2-Hexyne 24 A' 272 217 -55 1.256
C6H10 2-Hexyne 38 A" 392 246 -146 1.596
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.214
C4N2 2-Butynedinitrile 3 Σg 692 571 -121 1.212
CaO Calcium monoxide 1 Σ 732 505 -227 1.448
LiOH lithium hydroxide 3 Π 257 392 135 0.655
NaOH sodium hydroxide 3 Π 300 195 -105 1.537
ZnS Zinc sulfide 1 Σ 459 368 -91 1.247
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.602
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.412
C5H8 1,3-Pentadiene, (E)- 32 A" 129 186 57 0.694
C5H8 1,3-Pentadiene, (E)- 31 A" 361 235 -126 1.537
C2H5 Ethyl radical 9 A' 528 431 -97 1.226
CN Cyano radical 1 Σ 2069 2715 646 0.762
C2H Ethynyl radical 2 Σ 1841 2344 504 0.785
C2H Ethynyl radical 3 Π 372 764 392 0.487
CH3 Methyl radical 2 A2" 606 406 -200 1.493
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 87 -271 4.099
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 860 -276 1.321
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 114 -150 2.311
CH2CHO Vinyloxy radical 10 A" 703 1018 315 0.691
C4H6 Methylenecyclopropane 17 B1 360 257 -103 1.401
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.315
BF3+ boron trifluoride cation 3 E' 1662 2147 485 0.774
O2+ diatomic oxygen cation 1 Σg 1906 1408 -498 1.354
AsH3+ Arsine cation 2 A1 452 675 223 0.670
CaF2 Calcium difluoride 2 A1 120 60 -60 1.996
ZnCl Zinc monochloride 1 Σ 391 300 -90 1.300
PCl5 Phosphorus pentachloride 2 A1' 370 266 -104 1.393
O3 Ozone 3 B2 1042 2168 1126 0.481
NO Nitric oxide 1 Σ 1904 3382 1478 0.563
NO2 Nitrogen dioxide 3 B2 1618 2327 709 0.695
N2O4 Dinitrogen tetroxide 9 B2u 265 196 -69 1.352
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.384
Li2O dilithium oxide 3 Πu 112 61 -50 1.825
C3 carbon trimer 3 Πu 63 162 99 0.391
C5H5- cylopentadienyl anion 8 E1" 625 470 -155 1.329
C5H5- cylopentadienyl anion 14 E2" 600 445 -155 1.349
CaOH Calcium monohydroxide 2 Σ 353 626 273 0.564
CaOH Calcium monohydroxide 3 Π 609 359 -250 1.697
PS phosphorus sulfide 1 Σ 739 1284 545 0.576
ClNO2 Nitryl chloride 3 A1 364 278 -86 1.308
SiH- silicon monohydride anion 1 Σ 2175 1745 -430 1.247
H3O+ hydronium 2 A1 954 728 -226 1.311
ZnH Zinc monohydride 1 Σ 1608 1092 -516 1.473
PO Phosphorus monoxide 1 Σ 1233 3576 2343 0.345
AlO Aluminum monoxide 1 Σ 979 746 -234 1.314
FO2 Dioxygen monofluoride 3 A' 376 655 279 0.574
FO2 Dioxygen monofluoride 1 A' 1487 2710 1223 0.549
FO2 Dioxygen monofluoride 2 A' 579 1228 649 0.472
SCN thiocyanato radical 1 Σ 1942 2414 472 0.805
ClOO chloroperoxy radical 2 A' 414 1058 644 0.391
ClOO chloroperoxy radical 3 A' 201 488 287 0.413
NCO isocyanato radical 1 Σ 1921 2359 437 0.815
GeH2 germylene 2 A1 916 1843 927 0.497
GeH2 germylene 1 A1 1856 924 -932 2.008
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.901
ZnCH3 Zinc monomethyl 6 E 315 622 307 0.506