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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 MP2FU/6-31G**
Calculated values were scaled by 0.9344.

Species Name mode Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 428 -184 1.430
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 56 -19 1.336
CH3COOCH3 methyl acetate 27 A" 110 64 -46 1.706
C6H5CHO benzaldehyde 32 A" 688 483 -205 1.426
C6H4O2 parabenzoquinone 16 B2g 794 638 -156 1.245
C6H4O2 parabenzoquinone 30 B3u 109 84 -24 1.288
C3H6O 2-Propen-1-ol 21 A 554 423 -131 1.311
C6H5Cl chlorobenzene 18 B1 685 476 -209 1.438
C3H2N2 Malononitrile 6 A1 167 134 -33 1.250
C5H8 Cyclopentene 18 A' 254 174 -80 1.460
C2H4O3 trioxolane124 21 B 193 160 -33 1.203
C4H2 Diacetylene 8 Πu 630 513 -117 1.228
C6H5F Fluorobenzene 18 B1 685 498 -187 1.376
C2H3NO3 Oxamic acid 12 A' 687 570 -117 1.206
C2H3NO3 Oxamic acid 21 A" 162 59 -103 2.754
C3O2 Carbon suboxide 7 Πu 61 112 51 0.546
C6H4F2 1,4-difluorobenzene 16 B2g 692 488 -204 1.418
C5H8 1,4-Pentadiene 16 A 137 286 149 0.478
CO+ carbon monoxide cation 1 Σ 2214 2699 485 0.820
C3H6O2 1,3-Dioxolane 6 A 1361 2893 1532 0.471
C3H6O2 1,3-Dioxolane 13 A 658 1204 546 0.546
GeO2 Germanium dioxide 3 Πu 196 149 -47 1.316
NaOH sodium hydroxide 3 Π 300 169 -131 1.773
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.561
C2H Ethynyl radical 3 Π 372 768 396 0.484
C2Cl2 dichloroacetylene 4 Πg 333 135 -198 2.471
AsH3+ Arsine cation 2 A1 452 672 220 0.672
NO2 Nitrogen dioxide 3 B2 1618 2140 522 0.756
NS+ nitrogen sulfide cation 1 Σ 1415 1157 -258 1.223
Li2O dilithium oxide 3 Πu 112 58 -54 1.925
CaOH Calcium monohydroxide 3 Π 609 378 -231 1.613
PS phosphorus sulfide 1 Σ 739 1192 453 0.620
FO2 Dioxygen monofluoride 1 A' 1487 2738 1251 0.543
ClOO chloroperoxy radical 3 A' 201 465 263 0.433
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.205
O2+ diatomic oxygen cation 1 Σg 1906 1260 -645 1.512
BrF5 bromine pentafluoride 6 B2 281 215 -66 1.310
CaOH Calcium monohydroxide 2 Σ 353 597 244 0.591
Cu2 Copper dimer 1 Σg 265 388 123 0.683
FO2 Dioxygen monofluoride 3 A' 376 619 243 0.608
ClOO chloroperoxy radical 2 A' 414 1022 609 0.405
NCO isocyanato radical 1 Σ 1921 2344 423 0.820
GeH2 germylene 1 A1 1856 927 -929 2.002
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.319
ZnCH3 Zinc monomethyl 6 E 315 605 290 0.521
COBr2 Carbonic dibromide 6 B2 512 323 -189 1.585
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 325 -131 1.405
C5H8 1,3-Pentadiene, (E)- 31 A" 361 236 -125 1.527
CN Cyano radical 1 Σ 2069 2680 612 0.772
C2H Ethynyl radical 2 Σ 1841 2328 487 0.791
CH2CHO Vinyloxy radical 10 A" 703 1011 308 0.696
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.371
CH3COOH Acetic acid 11 A' 657 546 -111 1.203
CH3COCH3 Acetone 12 A2 77 53 -24 1.445
C2H6O2S Dimethyl sulfone 20 B1 262 218 -44 1.202
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 312 98 0.685
HCN+ hydrogen cyanide cation 2 Σ 1800 2767 967 0.651
CH3CCH propyne 9 E 633 524 -109 1.207
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.224
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 517 -115 1.222
C4H8O Furan, tetrahydro- 33 B 137 53 -84 2.571
C3H3NO Isoxazole 14 A" 1033 811 -222 1.273
C2H3N3 1H-1,2,4-Triazole 14 A" 990 824 -166 1.202
NH2CN cyanamide 5 A' 408 632 224 0.646
C2H3NO3 Oxamic acid 16 A" 984 762 -222 1.291
C2H3NO3 Oxamic acid 18 A" 745 601 -144 1.239
NO Nitric oxide 1 Σ 1904 3640 1735 0.523
C5H5- cylopentadienyl anion 14 E2" 600 499 -101 1.203
ZnH2 Zinc hydride 3 Πu 633 511 -121 1.237
AlO Aluminum monoxide 1 Σ 979 718 -261 1.364
FO2 Dioxygen monofluoride 2 A' 579 1173 594 0.494
SCN thiocyanato radical 1 Σ 1942 2388 446 0.813
GeH2 germylene 2 A1 916 1974 1058 0.464
C5H8 1,4-Pentadiene 17 A 102 81 -21 1.253
COBr2 Carbonic dibromide 4 B1 757 491 -266 1.542
C3H6O2 1,3-Dioxolane 4 A 1509 2917 1408 0.517
C2F2 difluoroacetylene 4 Πg 270 222 -48 1.214
C5H8 1,3-Pentadiene, (E)- 32 A" 129 190 61 0.677
C2Cl2+ dichloroacetylene cation 5 Πu 233 171 -62 1.362
C5H12 Pentane 23 A2 131 103 -28 1.269
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.223
C4H6O2 2,3-Butanedione 21 Bg 240 112 -128 2.138
C2H3NO3 Oxamic acid 3 A' 2600 3448 848 0.754
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 17 A" 815 647 -168 1.260
CH3CCCH3 2-Butyne 16 E" 371 239 -132 1.551
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3NH2 methyl amine 14 A" 1195 934 -261 1.279
HCN+ hydrogen cyanide cation 1 Σ 3050 3704 654 0.823
C6H4O2 parabenzoquinone 17 B2g 241 169 -72 1.428
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.763
O3 Ozone 3 B2 1042 2218 1176 0.470
NO+ nitric oxide cation 1 Σ 2377 1980 -397 1.200
N2O3 Dinitrogen trioxide 7 A' 205 168 -37 1.221
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.383
ClNO2 Nitryl chloride 3 A1 364 300 -63 1.211
SiH- silicon monohydride anion 1 Σ 2175 1809 -366 1.202
PO Phosphorus monoxide 1 Σ 1233 3802 2569 0.324
PN Phosphorus mononitride 1 Σ 1337 1081 -256 1.236
C5H8 1,4-Pentadiene 31 B 721 577 -144 1.249
C5H8 1,4-Pentadiene 33 B 331 93 -238 3.577
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.258
C6H8 1,4-Cyclohexadiene 19 B1u 108 78 -30 1.388
C6H8 1,4-Cyclohexadiene 23 B2g 403 330 -73 1.220
C3H6O2 1,3-Dioxolane 5 A 1480 2907 1427 0.509
CH3 Methyl radical 2 A2" 606 369 -238 1.645
BF3+ boron trifluoride cation 3 E' 1662 2143 481 0.775
CH3CCH propyne 10 E 328 268 -60 1.222
CBr2F2 Methane, dibromodifluoro- 3 A1 140 319 179 0.438
C6H5CN phenyl cyanide 19 B1 688 526 -162 1.309