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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 MP2FC/6-31G*
Calculated values were scaled by 0.943.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.698
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3COCH3 Acetone 12 A2 77 57 -20 1.348
C6H6 Benzene 8 B2g 703 477 -226 1.473
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 313 99 0.685
C2H2 Acetylene 4 Πg 612 353 -259 1.732
CH3NH2 methyl amine 14 A" 1195 945 -250 1.265
HCN+ hydrogen cyanide cation 2 Σ 1800 2789 989 0.645
HCN+ hydrogen cyanide cation 1 Σ 3050 3745 695 0.814
C2H5Br Ethyl bromide 5 A' 1451 2934 1483 0.495
C2H5Br Ethyl bromide 4 A' 1451 2988 1537 0.486
C2H5Br Ethyl bromide 8 A' 1061 1473 412 0.720
C2H5Br Ethyl bromide 10 A' 583 1462 879 0.399
C2H5Br Ethyl bromide 9 A' 964 1462 498 0.659
C2H5Br Ethyl bromide 6 A' 1386 2934 1548 0.472
C2H5Br Ethyl bromide 11 A' 290 1387 1097 0.209
CH3CCH propyne 9 E 633 486 -147 1.302
CH3CCH propyne 10 E 328 217 -111 1.511
CHONH2 formamide 12 A" 289 -129 -418 -2.239
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.225
CBr2F2 Methane, dibromodifluoro- 3 A1 140 320 180 0.437
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.209
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.327
CH3COOCH3 methyl acetate 27 A" 110 67 -43 1.641
C6H5NO2 Nitrobenzene 22 B1 675 470 -205 1.436
C6H5CN phenyl cyanide 19 B1 688 519 -169 1.325
C6H5CHO benzaldehyde 32 A" 688 478 -210 1.440
C6H4O2 parabenzoquinone 17 B2g 241 169 -72 1.425
C6H4O2 parabenzoquinone 30 B3u 109 85 -24 1.282
C6H4O2 parabenzoquinone 16 B2g 794 638 -156 1.245
CHCCH2CH3 1-Butyne 13 A' 634 524 -110 1.209
CHCCH2CH3 1-Butyne 22 A" 630 494 -136 1.276
C3H6O 2-Propen-1-ol 24 A 188 108 -81 1.748
C3H6O 2-Propen-1-ol 21 A 554 428 -126 1.296
C6H5Cl chlorobenzene 18 B1 685 462 -222 1.481
C3H2N2 Malononitrile 6 A1 167 133 -34 1.260
C4H8O Furan, tetrahydro- 33 B 137 40 -97 3.435
C4H4N2 Succinonitrile 17 Bg 387 320 -67 1.211
C5H8 Cyclopentene 18 A' 254 173 -81 1.471
C3H3NO Isoxazole 14 A" 1033 803 -230 1.286
C4H4N2 Pyridazine 13 A2 421 338 -83 1.247
CH2NN diazomethane 6 B1 406 -127 -533 -3.204
NH2CN cyanamide 5 A' 408 654 246 0.624
C4H6O2 2,3-Butanedione 21 Bg 240 120 -120 2.008
C4H6O2 2,3-Butanedione 9 Ag 614 506 -108 1.214
C4H2 Diacetylene 7 Πg 482 227 -255 2.127
C4H2 Diacetylene 8 Πu 630 425 -205 1.481
C6H5F Fluorobenzene 18 B1 685 491 -194 1.394
C2H3NO3 Oxamic acid 16 A" 984 759 -225 1.297
C2H3NO3 Oxamic acid 18 A" 745 606 -139 1.229
C2H3NO3 Oxamic acid 20 A" 315 257 -58 1.224
C2H3NO3 Oxamic acid 15 A' 328 260 -68 1.262
C2H3NO3 Oxamic acid 17 A" 815 655 -160 1.244
C2H3NO3 Oxamic acid 21 A" 162 52 -110 3.121
C2H3NO3 Oxamic acid 3 A' 2600 3423 823 0.760
CH3CCCH3 2-Butyne 16 E" 371 158 -213 2.348
C3H6O Oxetane 23 B2 1228 1009 -219 1.217
C3H6O Oxetane 12 A2 986 819 -167 1.204
C3H6O Oxetane 18 B1 90 -86 -176 -1.039
C3O2 Carbon suboxide 7 Πu 61 100 39 0.608
C6H4F2 1,4-difluorobenzene 16 B2g 692 478 -214 1.447
C5H8 1,4-Pentadiene 31 B 721 581 -140 1.242
C5H8 1,4-Pentadiene 33 B 331 93 -238 3.547
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.235
C5H8 1,4-Pentadiene 16 A 137 290 153 0.472
C6H10 1,5-Hexadiene 29 Bg 264 163 -101 1.617
C6H10 1,5-Hexadiene 14 Ag 351 263 -88 1.336
COBr2 Carbonic dibromide 6 B2 512 324 -188 1.583
COBr2 Carbonic dibromide 4 B1 757 489 -268 1.547
CH3SSCH3 Disulfide, dimethyl 13 A 117 94 -23 1.248
C6H8 1,4-Cyclohexadiene 19 B1u 108 80 -28 1.346
CO+ carbon monoxide cation 1 Σ 2214 2722 508 0.813
C3H6O2 1,3-Dioxolane 5 A 1480 2914 1434 0.508
C3H6O2 1,3-Dioxolane 4 A 1509 2919 1410 0.517
C3H6O2 1,3-Dioxolane 6 A 1361 2908 1547 0.468
C3H6O2 1,3-Dioxolane 13 A 658 1212 554 0.543
C2F2 difluoroacetylene 4 Πg 270 174 -96 1.555
C6H10 2-Hexyne 25 A' 115 84 -31 1.363
C6H10 2-Hexyne 24 A' 272 186 -86 1.465
C6H10 2-Hexyne 38 A" 392 239 -153 1.638
C6H10 2-Hexyne 40 A" 220 183 -37 1.203
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.221
C4N2 2-Butynedinitrile 3 Σg 692 573 -119 1.208
GeO2 Germanium dioxide 3 Πu 196 154 -41 1.269
NaOH sodium hydroxide 3 Π 300 116 -184 2.596
CH3OCH2CN Methoxyacetonitrile 15 A' 243 165 -78 1.472
CH3OCH2CN Methoxyacetonitrile 24 A" 113 83 -30 1.354
C5H8 1,3-Pentadiene, (E)- 32 A" 129 191 62 0.674
C5H8 1,3-Pentadiene, (E)- 31 A" 361 238 -123 1.517
C2H5 Ethyl radical 9 A' 528 437 -91 1.207
CN Cyano radical 1 Σ 2069 2699 631 0.766
C2H Ethynyl radical 2 Σ 1841 2342 502 0.786
C2H Ethynyl radical 3 Π 372 772 400 0.481
CH3 Methyl radical 2 A2" 606 376 -231 1.615
CH2OH Hydroxymethyl radical 9 A 234 436 202 0.537
CH2OH Hydroxymethyl radical 8 A 482 742 260 0.650
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 89 -269 4.006
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 864 -272 1.315
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 123 -141 2.141
CH2CHO Vinyloxy radical 10 A" 703 1016 313 0.692
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.371
C2Cl2+ dichloroacetylene cation 5 Πu 233 168 -65 1.385
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.204
BF3+ boron trifluoride cation 3 E' 1662 2153 492 0.772
O2+ diatomic oxygen cation 1 Σg 1906 1266 -640 1.506
SF4 Sulfur tetrafluoride 4 A1 228 187 -41 1.217
AsH3+ Arsine cation 2 A1 452 665 213 0.679
BrF5 bromine pentafluoride 6 B2 281 214 -67 1.316
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.327
O3 Ozone 3 B2 1042 2244 1201 0.464
NO Nitric oxide 1 Σ 1904 3691 1786 0.516
NO2 Nitrogen dioxide 3 B2 1618 2142 524 0.755
N2O4 Dinitrogen tetroxide 9 B2u 265 182 -83 1.457
N2O3 Dinitrogen trioxide 7 A' 205 169 -36 1.213
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.384
NS+ nitrogen sulfide cation 1 Σ 1415 1162 -253 1.218
Li2O dilithium oxide 3 Πu 112 62 -50 1.812
FO Oxygen monofluoride 1 Σ 1053 2348 1295 0.449
C3 carbon trimer 3 Πu 63 166 102 0.383
C5H5- cylopentadienyl anion 8 E1" 625 504 -121 1.239
C5H5- cylopentadienyl anion 14 E2" 600 480 -120 1.249
CaOH Calcium monohydroxide 2 Σ 353 603 250 0.585
CaOH Calcium monohydroxide 3 Π 609 377 -232 1.617
Cu2 Copper dimer 1 Σg 265 382 118 0.692
PS phosphorus sulfide 1 Σ 739 1180 441 0.626
ClNO2 Nitryl chloride 3 A1 364 302 -62 1.207
SiH- silicon monohydride anion 1 Σ 2175 1793 -382 1.213
ZnH2 Zinc hydride 3 Πu 633 494 -139 1.281
PO Phosphorus monoxide 1 Σ 1233 3868 2635 0.319
AlO Aluminum monoxide 1 Σ 979 724 -255 1.352
SCN thiocyanato radical 1 Σ 1942 2414 472 0.805
ClOO chloroperoxy radical 2 A' 414 1030 616 0.402
ClOO chloroperoxy radical 3 A' 201 468 267 0.430
PN Phosphorus mononitride 1 Σ 1337 1086 -251 1.231
NCO isocyanato radical 1 Σ 1921 2366 444 0.812
GeH2 germylene 2 A1 916 1785 869 0.513
GeH2 germylene 1 A1 1856 916 -940 2.027
Mg2 Magnesium diatomic 1 Σg 51 320 269 0.160
ZnCH3 Zinc monomethyl 6 E 315 605 290 0.520