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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 MP2/6-311G*
Calculated values were scaled by 0.9503.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 349 149 0.573
CH3OH Methyl alcohol 12 A" 200 349 149 0.572
CH3OH Methyl alcohol 12 A" 200 349 149 0.573
CH3OH Methyl alcohol 12 A" 200 349 149 0.572
CH3CONH2 Acetamide 20 A 259 380 121 0.681
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.695
CH3COOH Acetic acid 18 A" 93 71 -22 1.315
C6H6 Benzene 7 B2g 995 827 -168 1.203
C6H6 Benzene 8 B2g 703 379 -324 1.856
C2H6O2S Dimethyl sulfone 20 B1 262 213 -49 1.231
C2H2 Acetylene 4 Πg 612 377 -235 1.623
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 328 114 0.652
CH3CCH propyne 9 E 633 508 -125 1.246
CH3CCH propyne 10 E 328 227 -101 1.447
HCN+ hydrogen cyanide cation 1 Σ 3050 3690 640 0.827
HCN+ hydrogen cyanide cation 2 Σ 1800 2759 959 0.652
C3F8 perfluoropropane 13 A2 276 220 -56 1.254
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
C6H5CHO benzaldehyde 32 A" 688 411 -277 1.673
C9H8 Indene 40 A" 690 494 -196 1.397
C9H8 Indene 41 A" 549 371 -178 1.479
C6H4O2 parabenzoquinone 30 B3u 109 83 -26 1.311
C6H5CN phenyl cyanide 19 B1 688 527 -161 1.305
C6H5CN phenyl cyanide 20 B1 542 444 -98 1.220
C6H4O2 parabenzoquinone 17 B2g 241 159 -82 1.511
CHCCH2CH3 1-Butyne 22 A" 630 524 -106 1.203
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.708
C6H5Cl chlorobenzene 18 B1 685 422 -263 1.624
C6H5Cl chlorobenzene 19 B1 467 369 -98 1.265
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
C2H3N3 1H-1,2,4-Triazole 14 A" 990 816 -174 1.214
C4H4N2 Pyridazine 13 A2 421 334 -87 1.259
C6H5F Fluorobenzene 15 B1 997 824 -173 1.210
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.018
C4H6O2 2,3-Butanedione 9 Ag 614 507 -107 1.210
C6H5F Fluorobenzene 18 B1 685 507 -178 1.352
NH2CN cyanamide 5 A' 408 673 265 0.606
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 16 A 137 293 156 0.468
C5H8 1,4-Pentadiene 17 A 102 82 -20 1.238
COBr2 Carbonic dibromide 4 B1 757 498 -259 1.521
COBr2 Carbonic dibromide 6 B2 512 336 -176 1.522
C6H10 1,5-Hexadiene 14 Ag 351 262 -89 1.338
C6H10 1,5-Hexadiene 20 Au 649 541 -108 1.200
C6H10 1,5-Hexadiene 29 Bg 264 159 -105 1.665
CH3SSCH3 Disulfide, dimethyl 13 A 117 97 -20 1.204
C6H8 1,4-Cyclohexadiene 19 B1u 108 59 -49 1.826
C6H8 1,4-Cyclohexadiene 23 B2g 403 319 -84 1.263
CO+ carbon monoxide cation 1 Σ 2214 2739 525 0.808
CO+ carbon monoxide cation 1 Σ 2214 2739 525 0.808
CO+ carbon monoxide cation 1 Σ 2214 2739 525 0.808
CO+ carbon monoxide cation 1 Σ 2214 2739 525 0.808
CH2D2 methane-d2 6 B1 3013 2263 -750 1.331
CH2D2 methane-d2 8 B2 2234 3055 821 0.731
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.214
NaOH sodium hydroxide 3 Π 300 195 -105 1.537
LiOH lithium hydroxide 3 Π 257 392 135 0.655
CaO Calcium monoxide 1 Σ 732 505 -227 1.448
C4N2 2-Butynedinitrile 3 Σg 692 571 -121 1.212
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)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.412
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.412
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.412
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.412
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.602
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.596
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.602
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.596
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
CH3OO methylperoxy radical 12 A" 170 141 -29 1.202
CH3 Methyl radical 2 A2" 606 406 -200 1.493
CH3 Methyl radical 2 A2" 606 406 -200 1.493
CH3 Methyl radical 2 A2" 606 406 -200 1.493
CH3 Methyl radical 2 A2" 606 406 -200 1.493
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 114 -150 2.311
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 87 -271 4.099
CH2OH Hydroxymethyl radical 8 A 482 710 228 0.679
CH2OH Hydroxymethyl radical 9 A 234 461 227 0.507
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 860 -276 1.321
C4H6 Methylenecyclopropane 17 B1 360 257 -103 1.401
BF3+ boron trifluoride cation 3 E' 1662 2147 485 0.774
CH2CHO Vinyloxy radical 10 A" 703 1018 315 0.691
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.315
O2+ diatomic oxygen cation 1 Σg 1906 1408 -498 1.354
O2+ diatomic oxygen cation 1 Σg 1906 1408 -498 1.354
O2+ diatomic oxygen cation 1 Σg 1906 1408 -498 1.354
O2+ diatomic oxygen cation 1 Σg 1906 1408 -498 1.354
FOOF Perfluoroperoxide 3 A 360 233 -127 1.547
FOOF Perfluoroperoxide 4 A 202 127 -75 1.586
AsH3+ Arsine cation 2 A1 452 675 223 0.670
MgF2 Magnesium fluoride 3 Πu 165 135 -30 1.221
CaF2 Calcium difluoride 2 A1 120 60 -60 1.996
ZnCl Zinc monochloride 1 Σ 391 300 -90 1.300
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.384
PCl5 Phosphorus pentachloride 2 A1' 370 266 -104 1.393
O3 Ozone 3 B2 1042 2168 1126 0.481
C3 carbon trimer 3 Πu 63 162 99 0.391
C3 carbon trimer 3 Πu 63 163 100 0.388
C5H5- cylopentadienyl anion 8 E1" 625 470 -155 1.329
C5H5- cylopentadienyl anion 14 E2" 600 445 -155 1.349
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
Li2O dilithium oxide 3 Πu 112 61 -50 1.825
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
C3 carbon trimer 3 Πu 63 162 99 0.391
C3 carbon trimer 3 Πu 63 163 100 0.388
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
SiH- silicon monohydride anion 1 Σ 2175 1745 -430 1.247
SiH- silicon monohydride anion 1 Σ 2175 1745 -430 1.247
SiH- silicon monohydride anion 1 Σ 2175 1745 -430 1.247
SF5Cl sulfur chloropentafluoride 5 B1 625 457 -168 1.368
SF5Cl sulfur chloropentafluoride 7 B2 505 309 -196 1.636
SF5Cl sulfur chloropentafluoride 11 E 397 243 -154 1.631
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
PO Phosphorus monoxide 1 Σ 1233 3580 2346 0.345
PO Phosphorus monoxide 1 Σ 1233 3576 2343 0.345
PO Phosphorus monoxide 1 Σ 1233 3580 2346 0.345
ClOO chloroperoxy radical 2 A' 414 1058 644 0.391
ClOO chloroperoxy radical 3 A' 201 488 287 0.413
AlO Aluminum monoxide 1 Σ 979 746 -234 1.314
FO2 Dioxygen monofluoride 1 A' 1487 2710 1223 0.549
FO2 Dioxygen monofluoride 2 A' 579 1228 649 0.472
FO2 Dioxygen monofluoride 3 A' 376 655 279 0.574
SCN thiocyanato radical 1 Σ 1942 2414 472 0.805
GeH2 germylene 1 A1 1856 924 -932 2.008
GeH2 germylene 2 A1 916 1843 927 0.497
H2OH2O water dimer 7 A' 143 205 62 0.698
H2OH2O water dimer 11 A" 108 168 60 0.645
F3- trifluoride anion 1 Σg 461 378 -83 1.220
H2POH Phosphinous acid 9 A" 375 273 -102 1.375
AsN Arsenic mononitride 1 Σ 1069 818 -251 1.306
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.901
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.901
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.901
Mg2 Magnesium diatomic 1 Σg 51 27 -24 1.901
ZnCH3 Zinc monomethyl 6 E 315 622 307 0.506
NCO isocyanato radical 1 Σ 1921 2359 437 0.815
ONONO Nitrosyl nitrite 9 B2 380 219 -161 1.733