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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 0.9365.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 11 A' 657 546 -111 1.203
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
CH3COCH3 Acetone 12 A2 77 53 -24 1.455
C2H6O2S Dimethyl sulfone 20 B1 262 217 -45 1.207
C6H6 Benzene 8 B2g 703 468 -235 1.503
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 312 98 0.685
C2H2 Acetylene 4 Πg 612 416 -196 1.473
CH3NH2 methyl amine 14 A" 1195 935 -260 1.279
HCN+ hydrogen cyanide cation 2 Σ 1800 2775 975 0.649
HCN+ hydrogen cyanide cation 1 Σ 3050 3727 678 0.818
CH3CCH propyne 9 E 633 517 -116 1.225
CH3CCH propyne 10 E 328 255 -73 1.285
CH3COCl Acetyl Chloride 15 A" 166 135 -31 1.226
CBr2F2 Methane, dibromodifluoro- 3 A1 140 318 178 0.440
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 517 -115 1.222
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.306
CH3COCH2CH3 2-Butanone 33 A" 87 27 -60 3.164
CH3COOCH3 methyl acetate 27 A" 110 62 -48 1.767
C6H5CN phenyl cyanide 19 B1 688 511 -177 1.346
C6H5CHO benzaldehyde 32 A" 688 462 -226 1.488
C6H4O2 parabenzoquinone 17 B2g 241 159 -82 1.518
C6H4O2 parabenzoquinone 30 B3u 109 83 -25 1.304
C6H4O2 parabenzoquinone 16 B2g 794 619 -175 1.282
CHCCH2CH3 1-Butyne 22 A" 630 521 -109 1.209
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.754
C3H6O 2-Propen-1-ol 21 A 554 423 -131 1.311
C6H5Cl chlorobenzene 18 B1 685 450 -234 1.520
C5H12 Pentane 23 A2 131 103 -28 1.276
C3H2N2 Malononitrile 6 A1 167 132 -35 1.267
C4H8O Furan, tetrahydro- 33 B 137 51 -86 2.699
C4H4N2 Succinonitrile 17 Bg 387 317 -70 1.220
C5H8 Cyclopentene 18 A' 254 173 -81 1.466
C5H8 Cyclopentene 29 A" 1082 901 -181 1.201
C3H3NO Isoxazole 14 A" 1033 808 -225 1.278
C2H3N3 1H-1,2,4-Triazole 14 A" 990 821 -169 1.206
C2H4O3 trioxolane124 21 B 193 160 -33 1.206
C4H4N2 Pyridazine 13 A2 421 334 -87 1.261
NH2CN cyanamide 5 A' 408 637 229 0.641
C4H6O2 2,3-Butanedione 21 Bg 240 111 -129 2.160
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.223
C4H2 Diacetylene 8 Πu 630 500 -130 1.259
C6H5F Fluorobenzene 18 B1 685 481 -204 1.425
C2H3NO3 Oxamic acid 16 A" 984 751 -233 1.310
C2H3NO3 Oxamic acid 18 A" 745 600 -145 1.241
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 17 A" 815 646 -169 1.262
C2H3NO3 Oxamic acid 12 A' 687 569 -118 1.207
C2H3NO3 Oxamic acid 19 A" 481 400 -81 1.203
C2H3NO3 Oxamic acid 21 A" 162 53 -109 3.053
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
CH3CCCH3 2-Butyne 16 E" 371 214 -157 1.730
C3O2 Carbon suboxide 7 Πu 61 100 39 0.611
C6H4F2 1,4-difluorobenzene 16 B2g 692 455 -237 1.520
C5H8 1,4-Pentadiene 31 B 721 576 -145 1.251
C5H8 1,4-Pentadiene 33 B 331 93 -238 3.572
C5H8 1,4-Pentadiene 17 A 102 82 -20 1.247
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C6H10 1,5-Hexadiene 29 Bg 264 162 -102 1.632
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.351
COBr2 Carbonic dibromide 6 B2 512 321 -191 1.594
COBr2 Carbonic dibromide 4 B1 757 486 -271 1.558
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.263
C6H8 1,4-Cyclohexadiene 23 B2g 403 326 -77 1.235
C6H8 1,4-Cyclohexadiene 19 B1u 108 75 -33 1.447
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
C2F2 difluoroacetylene 4 Πg 270 172 -98 1.566
C6H10 2-Hexyne 25 A' 115 88 -27 1.309
C6H10 2-Hexyne 24 A' 272 210 -62 1.292
C6H10 2-Hexyne 38 A" 392 250 -142 1.568
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.234
C4N2 2-Butynedinitrile 3 Σg 692 569 -123 1.217
GeO2 Germanium dioxide 3 Πu 196 153 -42 1.278
NaOH sodium hydroxide 3 Π 300 111 -189 2.699
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 108 -63 1.580
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 323 -133 1.410
C5H8 1,3-Pentadiene, (E)- 32 A" 129 190 61 0.679
C5H8 1,3-Pentadiene, (E)- 31 A" 361 235 -126 1.535
CN Cyano radical 1 Σ 2069 2681 612 0.772
C2H Ethynyl radical 2 Σ 1841 2327 486 0.791
C2H Ethynyl radical 3 Π 372 762 390 0.488
CH3 Methyl radical 2 A2" 606 366 -241 1.658
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 89 -269 4.027
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 858 -278 1.324
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 120 -144 2.192
CH2CHO Vinyloxy radical 10 A" 703 1010 307 0.696
C4H6 Methylenecyclopropane 17 B1 360 259 -101 1.390
C2Cl2+ dichloroacetylene cation 5 Πu 233 167 -66 1.395
ClFO3 Perchloryl fluoride 6 E 405 334 -71 1.212
BF3+ boron trifluoride cation 3 E' 1662 2138 477 0.777
O2+ diatomic oxygen cation 1 Σg 1906 1257 -649 1.516
SF4 Sulfur tetrafluoride 4 A1 228 186 -42 1.223
AsH3+ Arsine cation 2 A1 452 678 226 0.666
BrF5 bromine pentafluoride 6 B2 281 212 -69 1.325
PCl5 Phosphorus pentachloride 2 A1' 370 277 -93 1.336
O3 Ozone 3 B2 1042 2228 1186 0.468
NO Nitric oxide 1 Σ 1904 3665 1761 0.520
NO+ nitric oxide cation 1 Σ 2377 1980 -397 1.200
NO2 Nitrogen dioxide 3 B2 1618 2127 509 0.761
N2O4 Dinitrogen tetroxide 9 B2u 265 180 -85 1.471
N2O3 Dinitrogen trioxide 7 A' 205 168 -37 1.221
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.385
NS+ nitrogen sulfide cation 1 Σ 1415 1154 -261 1.226
Li2O dilithium oxide 3 Πu 112 61 -50 1.824
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
C5H5- cylopentadienyl anion 8 E1" 625 515 -110 1.212
C5H5- cylopentadienyl anion 14 E2" 600 489 -111 1.226
CaOH Calcium monohydroxide 2 Σ 353 598 245 0.590
CaOH Calcium monohydroxide 3 Π 609 377 -232 1.614
Cu2 Copper dimer 1 Σg 265 380 115 0.697
PS phosphorus sulfide 1 Σ 739 1172 433 0.631
ClNO2 Nitryl chloride 3 A1 364 299 -64 1.215
SiH- silicon monohydride anion 1 Σ 2175 1808 -367 1.203
ZnH2 Zinc hydride 3 Πu 633 476 -156 1.328
PO Phosphorus monoxide 1 Σ 1233 3842 2608 0.321
AlO Aluminum monoxide 1 Σ 979 719 -260 1.362
FO2 Dioxygen monofluoride 3 A' 376 620 244 0.607
FO2 Dioxygen monofluoride 1 A' 1487 2752 1265 0.540
FO2 Dioxygen monofluoride 2 A' 579 1172 592 0.494
SCN thiocyanato radical 1 Σ 1942 2398 455 0.810
ClOO chloroperoxy radical 2 A' 414 1023 609 0.404
ClOO chloroperoxy radical 3 A' 201 465 264 0.433
PN Phosphorus mononitride 1 Σ 1337 1079 -258 1.239
NCO isocyanato radical 1 Σ 1921 2349 428 0.818
GeH2 germylene 2 A1 916 1978 1062 0.463
GeH2 germylene 1 A1 1856 932 -924 1.992
Mg2 Magnesium diatomic 1 Σg 51 318 267 0.161
ZnCH3 Zinc monomethyl 6 E 315 598 283 0.527