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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
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
HCN+ hydrogen cyanide cation 1 Σ 3050 3547 497 0.860
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
CH3COCl Acetyl Chloride 15 A" 166 123 -43 1.355
CBr2F2 Methane, dibromodifluoro- 3 A1 140 316 176 0.443
C6H4O2 parabenzoquinone 16 B2g 794 645 -149 1.231
C6H4O2 parabenzoquinone 17 B2g 241 172 -69 1.400
C6H4O2 parabenzoquinone 30 B3u 109 84 -24 1.285
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.205
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.193
C3H2N2 Malononitrile 6 A1 167 132 -35 1.270
NH2CN cyanamide 5 A' 408 673 265 0.606
NH2CN cyanamide 9 A" 435 360 -75 1.209
C6H5F Fluorobenzene 18 B1 685 504 -181 1.358
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
COBr2 Carbonic dibromide 4 B1 757 482 -275 1.571
COBr2 Carbonic dibromide 6 B2 512 316 -196 1.622
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.232
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
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
BeO beryllium oxide 1 Σ 1457 575 -883 2.536
CaO Calcium monoxide 1 Σ 732 1353 621 0.541
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
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
CN Cyano radical 1 Σ 2069 2567 498 0.806
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
C2H Ethynyl radical 2 Σ 1841 2298 457 0.801
C2H Ethynyl radical 3 Π 372 720 349 0.516
HCCF Fluoroacetylene 5 Π 367 277 -90 1.324
OH- hydroxide anion 1 Σ 3738 3264 -474 1.145
C4H6 Methylenecyclopropane 17 B1 360 260 -100 1.387
TiCl4 Titanium tetrachloride 1 A1 389 164 -225 2.373
TiCl4 Titanium tetrachloride 3 T2 498 400 -98 1.246
TiCl4 Titanium tetrachloride 4 T2 136 110 -26 1.238
C2Cl2+ dichloroacetylene cation 4 Πg 318 264 -54 1.204
C2Cl2+ dichloroacetylene cation 5 Πu 233 164 -69 1.418
PCl3 Phosphorus trichloride 3 E 482 176 -306 2.734
PCl3 Phosphorus trichloride 4 E 198 488 290 0.406
H2O2 Hydrogen peroxide 4 A 371 305 -66 1.217
SeO2 Selenium dioxide 1 A1 922 767 -155 1.202
SO2 Sulfur dioxide 1 A1 1151 930 -221 1.238
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
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
AsH3+ Arsine cation 2 A1 452 649 197 0.696
MgF2 Magnesium fluoride 3 Πu 165 136 -29 1.217
FOOF Perfluoroperoxide 1 A 1210 953 -257 1.270
SF4 Sulfur tetrafluoride 4 A1 228 186 -42 1.225
FO Oxygen monofluoride 1 Σ 1053 2519 1466 0.418
N2O3 Dinitrogen trioxide 5 A' 627 472 -155 1.327
N2O3 Dinitrogen trioxide 7 A' 205 156 -49 1.310
N2O3 Dinitrogen trioxide 9 A" 63 156 93 0.404
Cu2 Copper dimer 1 Σg 265 405 140 0.653
AsO Arsenic monoxide 1 Σ 967 738 -229 1.311
O3 Ozone 3 B2 1042 1530 488 0.681
NS+ nitrogen sulfide cation 1 Σ 1415 1009 -406 1.402
SiO Silicon monoxide 1 Σ 1242 937 -304 1.325
NO Nitric oxide 1 Σ 1904 3633 1729 0.524
NO+ nitric oxide cation 1 Σ 2377 1826 -551 1.302
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
PS+ phosphorus monosulfide cation 1 Σ 845 673 -172 1.256
C3 carbon trimer 3 Πu 63 169 105 0.376
C3 carbon trimer 3 Πu 63 169 105 0.376
ClNO2 Nitryl chloride 3 A1 364 267 -97 1.365
C3 carbon trimer 3 Πu 63 169 105 0.376
C3 carbon trimer 3 Πu 63 169 105 0.376
SF5Cl sulfur chloropentafluoride 11 E 397 237 -160 1.679
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 cation 1 Σ 1405 841 -564 1.671
SF5Cl sulfur chloropentafluoride 5 B1 625 442 -183 1.414
SF5Cl sulfur chloropentafluoride 7 B2 505 302 -203 1.672
SO+ sulfur monoxide cation 1 Σ 1360 1090 -270 1.248
HOClO Chlorous acid 4 A 592 479 -113 1.235
ZnH2 Zinc hydride 3 Πu 633 473 -159 1.336
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
Cl3- trichloride anion 2 Σu 327 263 -64 1.242
ClONO2 Chlorine nitrate 6 A' 434 340 -94 1.275
ClONO2 Chlorine nitrate 7 A' 273 224 -49 1.218
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
PN Phosphorus mononitride 1 Σ 1337 1082 -255 1.236
H2POH Phosphinous acid 9 A" 375 252 -124 1.491
BrONO Bromine nitrite 4 A' 391 304 -87 1.288
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
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
ZnCH3 Zinc monomethyl 6 E 315 607 292 0.519
GeO Germanium monoxide 1 Σ 986 501 -484 1.966
SSO Disulfur monoxide 1 A' 1166 957 -209 1.219
ONONO Nitrosyl nitrite 9 B2 380 235 -145 1.618
H2OH2O water dimer 11 A" 108 155 47 0.697