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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 MP4/6-31G*
Calculated values were scaled by 0.9548.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COCH3 Acetone 12 A2 77 56 -21 1.378
CH3OH Methyl alcohol 12 A" 200 333 133 0.600
CH3OH Methyl alcohol 12 A" 200 335 135 0.598
C2H2 Acetylene 4 Πg 612 299 -313 2.049
CH3OH Methyl alcohol 12 A" 200 333 133 0.600
CH3OH Methyl alcohol 12 A" 200 335 135 0.598
HCN+ hydrogen cyanide cation 2 Σ 1800 2741 941 0.657
CH3CCH propyne 9 E 633 470 -163 1.346
CH3CCH propyne 10 E 328 198 -130 1.654
HCN+ hydrogen cyanide cation 1 Σ 3050 3547 497 0.860
CH3COCl Acetyl Chloride 15 A" 166 123 -43 1.355
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.193
CBr2F2 Methane, dibromodifluoro- 3 A1 140 316 176 0.443
C6H4O2 parabenzoquinone 30 B3u 109 84 -24 1.285
C6H4O2 parabenzoquinone 16 B2g 794 645 -149 1.231
C6H4O2 parabenzoquinone 17 B2g 241 172 -69 1.400
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.205
C3H2N2 Malononitrile 6 A1 167 132 -35 1.270
C6H5F Fluorobenzene 18 B1 685 504 -181 1.358
NH2CN cyanamide 5 A' 408 673 265 0.606
NH2CN cyanamide 9 A" 435 360 -75 1.209
C4H6O2 2,3-Butanedione 9 Ag 614 501 -113 1.227
C4H6O2 2,3-Butanedione 21 Bg 240 112 -128 2.137
CH2NN diazomethane 6 B1 406 207 -199 1.960
C6H4F2 1,4-difluorobenzene 16 B2g 692 489 -203 1.415
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C5H8 1,4-Pentadiene 17 A 102 78 -24 1.301
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.232
CO+ carbon monoxide cation 1 Σ 2214 2628 414 0.843
CO+ carbon monoxide cation 1 Σ 2214 2628 414 0.843
CO+ carbon monoxide cation 1 Σ 2214 2628 414 0.843
CO+ carbon monoxide cation 1 Σ 2214 2628 414 0.843
MgO magnesium oxide 1 Σ 785 1173 388 0.669
GeO2 Germanium dioxide 3 Πu 196 140 -55 1.394
NaOH sodium hydroxide 3 Π 300 89 -211 3.390
COBr2 Carbonic dibromide 4 B1 757 482 -275 1.571
CH2D2 methane-d2 6 B1 3013 2256 -757 1.336
CH2D2 methane-d2 8 B2 2234 3045 811 0.734
C2F2 difluoroacetylene 4 Πg 270 66 -204 4.067
COBr2 Carbonic dibromide 6 B2 512 316 -196 1.622
BeO beryllium oxide 1 Σ 1457 575 -883 2.536
CaO Calcium monoxide 1 Σ 732 1353 621 0.541
CN Cyano radical 1 Σ 2069 2567 498 0.806
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.386
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.386
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 113 -58 1.508
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 113 -58 1.508
C2H5 Ethyl radical 9 A' 528 435 -93 1.214
C2H Ethynyl radical 2 Σ 1841 2298 457 0.801
C2H Ethynyl radical 3 Π 372 720 349 0.516
CH3OO methylperoxy radical 12 A" 170 137 -33 1.237
CH3 Methyl radical 2 A2" 606 399 -207 1.518
CH3 Methyl radical 2 A2" 606 399 -207 1.518
CH3 Methyl radical 2 A2" 606 399 -207 1.518
CH3 Methyl radical 2 A2" 606 399 -207 1.518
CH2OH Hydroxymethyl radical 8 A 482 726 244 0.664
CH2OH Hydroxymethyl radical 9 A 234 436 202 0.536
HCCF Fluoroacetylene 5 Π 367 277 -90 1.324
SeO2 Selenium dioxide 1 A1 922 767 -155 1.202
OH- hydroxide anion 1 Σ 3738 3264 -474 1.145
C2Cl2+ dichloroacetylene cation 4 Πg 318 264 -54 1.204
C2Cl2+ dichloroacetylene cation 5 Πu 233 164 -69 1.418
C4H6 Methylenecyclopropane 17 B1 360 260 -100 1.387
SOCl2 thionyl chloride 3 A' 344 286 -58 1.201
SOCl2 thionyl chloride 4 A' 194 160 -34 1.214
SOCl2 thionyl chloride 5 A" 455 379 -76 1.202
SO2 Sulfur dioxide 1 A1 1151 930 -221 1.238
H2O2 Hydrogen peroxide 4 A 371 305 -66 1.217
TiCl4 Titanium tetrachloride 1 A1 389 164 -225 2.373
O2+ diatomic oxygen cation 1 Σg 1906 1442 -464 1.322
O2+ diatomic oxygen cation 1 Σg 1906 1442 -464 1.322
O2+ diatomic oxygen cation 1 Σg 1906 1442 -464 1.322
O2+ diatomic oxygen cation 1 Σg 1906 1442 -464 1.322
TiCl4 Titanium tetrachloride 3 T2 498 400 -98 1.246
TiCl4 Titanium tetrachloride 4 T2 136 110 -26 1.238
MgF2 Magnesium fluoride 3 Πu 165 136 -29 1.217
PCl3 Phosphorus trichloride 3 E 482 176 -306 2.734
PCl3 Phosphorus trichloride 4 E 198 488 290 0.406
SF4 Sulfur tetrafluoride 4 A1 228 186 -42 1.225
SiO Silicon monoxide 1 Σ 1242 937 -304 1.325
AsH3+ Arsine cation 2 A1 452 649 197 0.696
N2O3 Dinitrogen trioxide 9 A" 63 156 93 0.404
FOOF Perfluoroperoxide 1 A 1210 953 -257 1.270
NS+ nitrogen sulfide cation 1 Σ 1415 1009 -406 1.402
FO Oxygen monofluoride 1 Σ 1053 2519 1466 0.418
C3 carbon trimer 3 Πu 63 169 105 0.376
C3 carbon trimer 3 Πu 63 169 105 0.376
C3 carbon trimer 3 Πu 63 169 105 0.376
C3 carbon trimer 3 Πu 63 169 105 0.376
O3 Ozone 3 B2 1042 1530 488 0.681
Cu2 Copper dimer 1 Σg 265 405 140 0.653
PS+ phosphorus monosulfide cation 1 Σ 845 673 -172 1.256
NO Nitric oxide 1 Σ 1904 3633 1729 0.524
NO+ nitric oxide cation 1 Σ 2377 1826 -551 1.302
N2O3 Dinitrogen trioxide 5 A' 627 472 -155 1.327
N2O3 Dinitrogen trioxide 7 A' 205 156 -49 1.310
AsO Arsenic monoxide 1 Σ 967 738 -229 1.311
C5H5- cylopentadienyl anion 8 E1" 625 512 -113 1.221
C5H5- cylopentadienyl anion 14 E2" 600 495 -105 1.211
CaOH Calcium monohydroxide 2 Σ 353 606 253 0.583
CaOH Calcium monohydroxide 3 Π 609 375 -234 1.625
ClNO2 Nitryl chloride 3 A1 364 267 -97 1.365
SiH- silicon monohydride anion 1 Σ 2175 1758 -417 1.237
SiH- silicon monohydride anion 1 Σ 2175 1758 -417 1.237
SiH- silicon monohydride anion 1 Σ 2175 1758 -417 1.237
SiH- silicon monohydride anion 1 Σ 2175 1758 -417 1.237
PO Phosphorus monoxide 1 Σ 1233 5459 4225 0.226
PO Phosphorus monoxide 1 Σ 1233 5459 4225 0.226
AlO Aluminum monoxide 1 Σ 979 10184 9204 0.096
SF5Cl sulfur chloropentafluoride 5 B1 625 442 -183 1.414
SF5Cl sulfur chloropentafluoride 7 B2 505 302 -203 1.672
SF5Cl sulfur chloropentafluoride 11 E 397 237 -160 1.679
HOClO Chlorous acid 4 A 592 479 -113 1.235
PN Phosphorus mononitride 1 Σ 1337 1082 -255 1.236
ZnH2 Zinc hydride 3 Πu 633 473 -159 1.336
PO+ phosphorus monoxide cation 1 Σ 1405 841 -564 1.671
SO+ sulfur monoxide cation 1 Σ 1360 1090 -270 1.248
GeO Germanium monoxide 1 Σ 986 501 -484 1.966
CSe Carbon monoselenide 1 Σ 1035 848 -188 1.221
ClOO chloroperoxy radical 2 A' 414 1031 617 0.401
ClOO chloroperoxy radical 3 A' 201 478 277 0.421
H2OH2O water dimer 11 A" 108 155 47 0.697
Cl3- trichloride anion 2 Σu 327 263 -64 1.242
H2POH Phosphinous acid 9 A" 375 252 -124 1.491
Mg2 Magnesium diatomic 1 Σg 51 234 183 0.219
Mg2 Magnesium diatomic 1 Σg 51 234 183 0.219
Mg2 Magnesium diatomic 1 Σg 51 234 183 0.219
Mg2 Magnesium diatomic 1 Σg 51 234 183 0.219
ClONO2 Chlorine nitrate 6 A' 434 340 -94 1.275
ClONO2 Chlorine nitrate 7 A' 273 224 -49 1.218
SSO Disulfur monoxide 1 A' 1166 957 -209 1.219
GeH2 germylene 1 A1 1856 897 -959 2.070
GeH2 germylene 2 A1 916 1741 825 0.526
F3- trifluoride anion 1 Σg 461 333 -128 1.384
AsN Arsenic mononitride 1 Σ 1069 719 -350 1.486
ZnCH3 Zinc monomethyl 6 E 315 607 292 0.519
BrONO Bromine nitrite 4 A' 391 304 -87 1.288
ONONO Nitrosyl nitrite 9 B2 380 235 -145 1.618