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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 MP2/6-31G(2df,p)
Calculated values were scaled by 0.9445.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.692
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.255
CH3COCH3 Acetone 12 A2 77 62 -15 1.247
CH3OH Methyl alcohol 12 A" 200 317 117 0.631
CH3OH Methyl alcohol 12 A" 200 314 114 0.637
CH3OH Methyl alcohol 12 A" 200 317 117 0.631
CH3OH Methyl alcohol 12 A" 200 314 114 0.637
C2H2 Acetylene 4 Πg 612 476 -136 1.285
HCN+ hydrogen cyanide cation 1 Σ 3050 3591 541 0.849
HCN+ hydrogen cyanide cation 2 Σ 1800 2729 929 0.660
CBr2F2 Methane, dibromodifluoro- 3 A1 140 339 199 0.414
C3F8 perfluoropropane 13 A2 276 212 -64 1.300
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.219
CH3COCH2CH3 2-Butanone 33 A" 87 38 -49 2.265
CH3COOCH3 methyl acetate 27 A" 110 62 -48 1.781
C6H4O2 parabenzoquinone 30 B3u 109 86 -23 1.262
C3H6O 2-Propen-1-ol 22 A 377 312 -65 1.208
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.741
C5H12 Pentane 23 A2 131 104 -27 1.256
C3H2N2 Malononitrile 6 A1 167 136 -31 1.231
C5H8 Cyclopentene 18 A' 254 175 -79 1.454
C2H4O3 trioxolane124 21 B 193 159 -34 1.214
C4H4N2 Pyridazine 13 A2 421 350 -71 1.204
CH2NN diazomethane 6 B1 406 110 -296 3.683
C4H6O2 2,3-Butanedione 21 Bg 240 118 -122 2.027
C4H2 Diacetylene 7 Πg 482 390 -92 1.235
C4H2 Diacetylene 8 Πu 630 513 -117 1.227
NH2CN cyanamide 5 A' 408 643 235 0.634
C4H6O2 2,3-Butanedione 9 Ag 614 501 -113 1.225
C4H6O2 2,3-Butanedione 13 Au 1111 914 -197 1.216
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.278
C2H3NO3 Oxamic acid 16 A" 984 797 -187 1.234
C2H3NO3 Oxamic acid 17 A" 815 656 -159 1.242
C2H3NO3 Oxamic acid 18 A" 745 616 -129 1.210
C2H3NO3 Oxamic acid 21 A" 162 66 -96 2.438
C6H10 1,5-Hexadiene 29 Bg 264 179 -85 1.475
C5H8 1,4-Pentadiene 15 A 421 349 -72 1.205
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.232
COBr2 Carbonic dibromide 4 B1 757 513 -244 1.476
COBr2 Carbonic dibromide 6 B2 512 342 -170 1.499
C6H10 1,5-Hexadiene 14 Ag 351 258 -93 1.358
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 186 -41 1.221
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.233
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
CH2D2 methane-d2 6 B1 3013 2275 -738 1.325
CH2D2 methane-d2 8 B2 2234 3071 837 0.727
C2F2 difluoroacetylene 4 Πg 270 204 -66 1.323
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.251
NaOH sodium hydroxide 3 Π 300 213 -87 1.408
C4N2 2-Butynedinitrile 3 Σg 692 572 -120 1.209
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 338 -118 1.349
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 124 -47 1.379
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 211 67 0.681
CH3OCH2CN Methoxyacetonitrile 15 A' 243 169 -74 1.434
CH3OCH2CN Methoxyacetonitrile 24 A" 113 85 -28 1.323
C2H5 Ethyl radical 9 A' 528 427 -101 1.236
CN Cyano radical 1 Σ 2069 2729 660 0.758
C2H Ethynyl radical 2 Σ 1841 2386 545 0.771
C2H Ethynyl radical 3 Π 372 821 449 0.453
C2H+ Ethynyl cation 3 Π 550 804 254 0.684
CH3OO methylperoxy radical 12 A" 170 127 -43 1.342
CH3 Methyl radical 2 A2" 606 384 -222 1.579
CH3 Methyl radical 2 A2" 606 384 -222 1.579
CH3 Methyl radical 2 A2" 606 384 -222 1.579
CH3 Methyl radical 2 A2" 606 384 -222 1.579
CH2OH Hydroxymethyl radical 8 A 482 693 211 0.695
CH2OH Hydroxymethyl radical 9 A 234 431 197 0.543
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 853 -283 1.332
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 140 -124 1.886
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 96 -262 3.729
CH2CHO Vinyloxy radical 10 A" 703 1028 325 0.684
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.290
C2Cl2+ dichloroacetylene cation 5 Πu 233 181 -52 1.286
O2+ diatomic oxygen cation 1 Σg 1906 1416 -490 1.346
O2+ diatomic oxygen cation 1 Σg 1906 1416 -490 1.346
O2+ diatomic oxygen cation 1 Σg 1906 1416 -490 1.346
O2+ diatomic oxygen cation 1 Σg 1906 1416 -490 1.346
GaF3 Gallium trifluoride 4 E' 192 133 -59 1.447
FOOF Perfluoroperoxide 1 A 1210 999 -211 1.211
ZnCN Zinc monocyanide 3 Π 212 115 -97 1.841
CaF2 Calcium difluoride 2 A1 120 87 -33 1.377
O3 Ozone 3 B2 1042 2090 1048 0.499
NO2 Nitrogen dioxide 3 B2 1618 3456 1838 0.468
C3 carbon trimer 3 Πu 63 211 148 0.301
C3 carbon trimer 3 Πu 63 211 148 0.301
C3 carbon trimer 3 Πu 63 211 148 0.301
C3 carbon trimer 3 Πu 63 211 148 0.301
PCl5 Phosphorus pentachloride 2 A1' 370 286 -84 1.293
NO Nitric oxide 1 Σ 1904 3260 1356 0.584
Cu2 Copper dimer 1 Σg 265 401 137 0.659
N2O4 Dinitrogen tetroxide 9 B2u 265 191 -74 1.387
FO Oxygen monofluoride 1 Σ 1053 2586 1533 0.407
FO Oxygen monofluoride 1 Σ 1053 2586 1533 0.407
CaOH Calcium monohydroxide 2 Σ 353 617 264 0.572
CaOH Calcium monohydroxide 3 Π 609 371 -238 1.641
N2O3 Dinitrogen trioxide 9 A" 63 169 106 0.374
SO+ sulfur monoxide cation 1 Σ 1360 1129 -231 1.205
AlO Aluminum monoxide 1 Σ 979 708 -272 1.384
ClOO chloroperoxy radical 2 A' 414 1069 656 0.387
ClOO chloroperoxy radical 3 A' 201 479 278 0.420
PN Phosphorus mononitride 1 Σ 1337 1113 -224 1.202
SF5Cl sulfur chloropentafluoride 5 B1 625 473 -152 1.320
SF5Cl sulfur chloropentafluoride 7 B2 505 321 -184 1.573
SF5Cl sulfur chloropentafluoride 11 E 397 255 -142 1.559
GeH2 germylene 1 A1 1856 936 -920 1.983
AsN Arsenic mononitride 1 Σ 1069 888 -181 1.203
Mg2 Magnesium diatomic 1 Σg 51 322 271 0.159
Mg2 Magnesium diatomic 1 Σg 51 322 271 0.159
Mg2 Magnesium diatomic 1 Σg 51 322 271 0.159
Mg2 Magnesium diatomic 1 Σg 51 322 271 0.159
ZnCH3 Zinc monomethyl 6 E 315 581 266 0.542
ZnH2 Zinc hydride 3 Πu 633 386 -246 1.639
NCO isocyanato radical 1 Σ 1921 2349 428 0.818
Al2 Aluminum diatomic 1 Σg 286 456 171 0.626
H2OH2O water dimer 12 A" 88 37 -51 2.394
H2POH Phosphinous acid 9 A" 375 264 -112 1.424
ONONO Nitrosyl nitrite 9 B2 380 285 -95 1.336