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

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 11 A' 657 546 -111 1.203
C2H6O2S Dimethyl sulfone 20 B1 262 218 -44 1.202
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
HCN+ hydrogen cyanide cation 1 Σ 3050 3704 654 0.823
HCN+ hydrogen cyanide cation 2 Σ 1800 2767 967 0.651
CH3COCH3 Acetone 12 A2 77 53 -24 1.445
C2H2 Acetylene 4 Πg 612 428 -184 1.430
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 312 98 0.685
CH3CCH propyne 9 E 633 524 -109 1.207
CH3CCH propyne 10 E 328 268 -60 1.222
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.224
CBr2F2 Methane, dibromodifluoro- 3 A1 140 319 179 0.438
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 56 -19 1.336
C3F8 perfluoropropane 13 A2 276 210 -66 1.316
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 517 -115 1.222
C9H8 Indene 40 A" 690 504 -187 1.371
C9H8 Indene 41 A" 549 439 -109 1.249
CH3COOCH3 methyl acetate 27 A" 110 64 -46 1.706
C6H4O2 parabenzoquinone 30 B3u 109 84 -24 1.288
C6H5CN phenyl cyanide 19 B1 688 526 -162 1.309
C6H5CHO benzaldehyde 32 A" 688 483 -205 1.426
C6H4O2 parabenzoquinone 16 B2g 794 638 -156 1.245
C6H4O2 parabenzoquinone 17 B2g 241 169 -72 1.428
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.763
C6H5Cl chlorobenzene 18 B1 685 476 -209 1.438
C5H12 Pentane 23 A2 131 103 -28 1.269
C3H2N2 Malononitrile 6 A1 167 134 -33 1.250
C5H8 Cyclopentene 18 A' 254 174 -80 1.460
C2H3N3 1H-1,2,4-Triazole 14 A" 990 824 -166 1.202
C2H4O3 trioxolane124 21 B 193 160 -33 1.203
C4H2 Diacetylene 8 Πu 630 513 -117 1.228
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.223
C4H6O2 2,3-Butanedione 21 Bg 240 112 -128 2.138
NH2CN cyanamide 5 A' 408 632 224 0.646
C6H5F Fluorobenzene 18 B1 685 498 -187 1.376
C2H3NO3 Oxamic acid 3 A' 2600 3448 848 0.754
C2H3NO3 Oxamic acid 12 A' 687 570 -117 1.206
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 16 A" 984 762 -222 1.291
C2H3NO3 Oxamic acid 17 A" 815 647 -168 1.260
C2H3NO3 Oxamic acid 18 A" 745 601 -144 1.239
C2H3NO3 Oxamic acid 21 A" 162 59 -103 2.754
C6H4F2 1,4-difluorobenzene 16 B2g 692 488 -204 1.418
CH3CCCH3 2-Butyne 16 E" 371 239 -132 1.551
C3O2 Carbon suboxide 7 Πu 61 112 51 0.546
COBr2 Carbonic dibromide 4 B1 757 491 -266 1.542
COBr2 Carbonic dibromide 6 B2 512 323 -189 1.585
C5H8 1,4-Pentadiene 17 A 102 81 -21 1.253
C5H8 1,4-Pentadiene 16 A 137 286 149 0.478
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.258
CO+ carbon monoxide cation 1 Σ 2214 2699 485 0.820
CO+ carbon monoxide cation 1 Σ 2214 2699 485 0.820
CO+ carbon monoxide cation 1 Σ 2214 2699 485 0.820
CO+ carbon monoxide cation 1 Σ 2214 2699 485 0.820
CH2D2 methane-d2 6 B1 3013 2272 -741 1.326
CH2D2 methane-d2 8 B2 2234 3067 833 0.728
C2F2 difluoroacetylene 4 Πg 270 222 -48 1.214
C6H8 1,4-Cyclohexadiene 19 B1u 108 78 -30 1.388
C6H8 1,4-Cyclohexadiene 23 B2g 403 330 -73 1.220
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)- 31 A" 456 325 -131 1.405
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 324 -132 1.406
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 325 -131 1.405
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 324 -132 1.406
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.561
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 109 -62 1.563
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.561
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 109 -62 1.563
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C2H Ethynyl radical 2 Σ 1841 2328 487 0.791
C2H Ethynyl radical 3 Π 372 768 396 0.484
CH3OO methylperoxy radical 12 A" 170 124 -46 1.369
CN Cyano radical 1 Σ 2069 2680 612 0.772
CH3 Methyl radical 2 A2" 606 369 -238 1.645
CH3 Methyl radical 2 A2" 606 369 -238 1.645
CH3 Methyl radical 2 A2" 606 369 -238 1.645
CH3 Methyl radical 2 A2" 606 369 -238 1.645
CH2OH Hydroxymethyl radical 9 A 234 431 197 0.543
CH2OH Hydroxymethyl radical 8 A 482 732 250 0.658
CH2CHO Vinyloxy radical 10 A" 703 1011 308 0.696
C2Cl2+ dichloroacetylene cation 5 Πu 233 171 -62 1.362
C2Cl2 dichloroacetylene 4 Πg 333 135 -198 2.471
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.371
O2+ diatomic oxygen cation 1 Σg 1906 1260 -645 1.512
O2+ diatomic oxygen cation 1 Σg 1906 1260 -645 1.512
O2+ diatomic oxygen cation 1 Σg 1906 1260 -645 1.512
O2+ diatomic oxygen cation 1 Σg 1906 1260 -645 1.512
ClFO3 Perchloryl fluoride 6 E 405 336 -69 1.205
BF3+ boron trifluoride cation 3 E' 1662 2143 481 0.775
BrF5 bromine pentafluoride 6 B2 281 215 -66 1.310
FOOF Perfluoroperoxide 1 A 1210 945 -265 1.281
AsH3+ Arsine cation 2 A1 452 672 220 0.672
NO2 Nitrogen dioxide 3 B2 1618 2140 522 0.756
N2O3 Dinitrogen trioxide 7 A' 205 168 -37 1.221
N2O3 Dinitrogen trioxide 9 A" 63 164 101 0.383
C3 carbon trimer 3 Πu 63 177 114 0.357
O3 Ozone 3 B2 1042 2218 1176 0.470
CaOH Calcium monohydroxide 2 Σ 353 597 244 0.591
CaOH Calcium monohydroxide 3 Π 609 378 -231 1.613
NO Nitric oxide 1 Σ 1904 3640 1735 0.523
NO+ nitric oxide cation 1 Σ 2377 1980 -397 1.200
PS phosphorus sulfide 1 Σ 739 1192 453 0.620
NS+ nitrogen sulfide cation 1 Σ 1415 1157 -258 1.223
Li2O dilithium oxide 3 Πu 112 58 -54 1.925
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
FO Oxygen monofluoride 1 Σ 1053 2331 1278 0.452
Cu2 Copper dimer 1 Σg 265 388 123 0.683
ClNO2 Nitryl chloride 3 A1 364 300 -63 1.211
C5H5- cylopentadienyl anion 14 E2" 600 499 -101 1.203
AlO Aluminum monoxide 1 Σ 979 718 -261 1.364
SiH- silicon monohydride anion 1 Σ 2175 1809 -366 1.202
SiH- silicon monohydride anion 1 Σ 2175 1810 -365 1.201
SiH- silicon monohydride anion 1 Σ 2175 1809 -366 1.202
SiH- silicon monohydride anion 1 Σ 2175 1810 -365 1.201
SF5Cl sulfur chloropentafluoride 5 B1 625 444 -181 1.407
SF5Cl sulfur chloropentafluoride 7 B2 505 302 -203 1.670
SF5Cl sulfur chloropentafluoride 11 E 397 239 -158 1.662
SCN thiocyanato radical 1 Σ 1942 2388 446 0.813
PN Phosphorus mononitride 1 Σ 1337 1081 -256 1.236
ZnH2 Zinc hydride 3 Πu 633 511 -121 1.237
PO Phosphorus monoxide 1 Σ 1233 3802 2569 0.324
PO Phosphorus monoxide 1 Σ 1233 3802 2569 0.324
PO Phosphorus monoxide 1 Σ 1233 3802 2569 0.324
PO Phosphorus monoxide 1 Σ 1233 3802 2569 0.324
FO2 Dioxygen monofluoride 1 A' 1487 2738 1251 0.543
FO2 Dioxygen monofluoride 2 A' 579 1173 594 0.494
FO2 Dioxygen monofluoride 3 A' 376 619 243 0.608
ClOO chloroperoxy radical 2 A' 414 1022 609 0.405
ClOO chloroperoxy radical 3 A' 201 465 263 0.433
ZnCH3 Zinc monomethyl 6 E 315 605 290 0.521
NNS Nitrogen sulfide 1 Σ 2048 1700 -348 1.205
NCO isocyanato radical 1 Σ 1921 2344 423 0.820
GeH2 germylene 1 A1 1856 927 -929 2.002
GeH2 germylene 2 A1 916 1974 1058 0.464
H2POH Phosphinous acid 9 A" 375 256 -119 1.467
AsN Arsenic mononitride 1 Σ 1069 823 -245 1.298
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.319
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.319
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.319
Mg2 Magnesium diatomic 1 Σg 51 22 -29 2.319
ONONO Nitrosyl nitrite 9 B2 380 257 -123 1.481