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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 mPW1PW91/3-21G*
Calculated values were scaled by 0.9496.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COCH3 Acetone 12 A2 77 61 -16 1.267
CH3COOH Acetic acid 11 A' 657 542 -115 1.211
CH3CONH2 Acetamide 20 A 259 397 139 0.651
CH3OH Methyl alcohol 12 A" 200 359 159 0.558
CH3OH Methyl alcohol 12 A" 200 367 167 0.545
CH3OH Methyl alcohol 12 A" 200 359 159 0.558
CH3OH Methyl alcohol 12 A" 200 367 167 0.545
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.217
CHONH2 formamide 12 A" 289 495 206 0.584
HNCO Isocyanic acid 4 A' 777 574 -202 1.352
HNCO Isocyanic acid 5 A' 577 427 -150 1.352
CBr2F2 Methane, dibromodifluoro- 3 A1 140 326 186 0.430
C3F8 perfluoropropane 13 A2 276 200 -76 1.382
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.220
C2H2O2 Ethanedial 7 Au 127 194 67 0.656
CH3OCHO methyl formate 18 A" 130 76 -54 1.711
C3H6O 2-Propen-1-ol 22 A 377 297 -81 1.272
C3H6O 2-Propen-1-ol 24 A 188 98 -90 1.914
C4H8O2 1,4-Dioxane 19 Au 288 220 -68 1.311
C5H8 Cyclopentene 18 A' 254 126 -128 2.014
C2H4O3 trioxolane124 21 B 193 160 -33 1.206
N2H4 Hydrazine 6 A 780 603 -177 1.293
N2H4 Hydrazine 12 B 966 791 -175 1.222
C4H6O2 2,3-Butanedione 16 Au 48 36 -12 1.332
C4H6O2 2,3-Butanedione 21 Bg 240 61 -179 3.955
C2N2 Cyanogen 4 Πg 503 755 252 0.666
C5H12 Propane, 2,2-dimethyl- 12 T1 203 317 114 0.640
C3H6O Oxetane 23 B2 1228 952 -276 1.290
C2H3NO3 Oxamic acid 3 A' 2600 3381 781 0.769
HCNO fulminic acid 5 Π 224 528 304 0.425
C2H3NO3 Oxamic acid 15 A' 328 253 -75 1.297
C2H3NO3 Oxamic acid 17 A" 815 665 -150 1.225
C2H3NO3 Oxamic acid 21 A" 162 113 -49 1.427
C3O2 Carbon suboxide 7 Πu 61 145 84 0.420
C3H6O Oxetane 7 A1 1018 841 -177 1.211
Zn(CH3)2 dimethyl zinc 11 E' 134 -100 -234 -1.340
C5H8 1,4-Pentadiene 16 A 137 298 161 0.459
C5H8 1,4-Pentadiene 17 A 102 77 -25 1.316
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.349
C6H10 1,5-Hexadiene 29 Bg 264 170 -94 1.555
COBr2 Carbonic dibromide 4 B1 757 523 -234 1.448
COBr2 Carbonic dibromide 6 B2 512 338 -174 1.515
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.212
CH2D2 methane-d2 6 B1 3013 2236 -777 1.348
CH2D2 methane-d2 8 B2 2234 3022 788 0.739
C4N2 2-Butynedinitrile 6 Πg 504 904 400 0.557
C4N2 2-Butynedinitrile 8 Πu 472 681 209 0.693
LiOH lithium hydroxide 3 Π 257 403 146 0.637
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 219 75 0.658
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.659
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 219 75 0.658
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.659
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.332
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.336
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.332
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.336
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 137 -34 1.244
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 136 -35 1.257
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 137 -34 1.244
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 136 -35 1.257
CCl2 dichloromethylene 3 B2 758 611 -147 1.241
C2H5 Ethyl radical 9 A' 528 439 -89 1.203
C2H Ethynyl radical 3 Π 372 544 172 0.684
CH3OO methylperoxy radical 12 A" 170 135 -35 1.262
CH3 Methyl radical 2 A2" 606 475 -132 1.278
CH3 Methyl radical 2 A2" 606 475 -132 1.278
CH3 Methyl radical 2 A2" 606 475 -132 1.278
CH3 Methyl radical 2 A2" 606 475 -132 1.278
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 95 -263 3.766
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 142 -122 1.864
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 863 -273 1.317
CH2OH Hydroxymethyl radical 9 A 234 399 165 0.587
OH- hydroxide anion 1 Σ 3738 2667 -1072 1.402
OH Hydroxyl radical 1 Σ 3738 3177 -561 1.177
OH+ hydoxyl cation 1 Σ 3113 2596 -517 1.199
NF2 Difluoroamino radical 2 A1 573 460 -113 1.246
HF Hydrogen fluoride 1 Σ 4138 3544 -594 1.168
O2+ diatomic oxygen cation 1 Σg 1906 1440 -466 1.324
O2+ diatomic oxygen cation 1 Σg 1906 1440 -466 1.324
O2+ diatomic oxygen cation 1 Σg 1906 1440 -466 1.324
O2+ diatomic oxygen cation 1 Σg 1906 1440 -466 1.324
C2Cl2 dichloroacetylene 4 Πg 333 499 166 0.667
HClO4 perchloric acid 12 A" 191 130 -61 1.465
HNO3 Nitric acid 7 A' 579 482 -97 1.201
H2SO4 Sulfuric acid 15 B 288 231 -56 1.244
H2SO4 Sulfuric acid 8 A 224 179 -45 1.251
NH3 Ammonia 2 A1 950 691 -259 1.375
AsH3+ Arsine cation 2 A1 452 685 233 0.660
BF3+ boron trifluoride cation 4 E' 411 -221 -632 -1.860
BF3+ boron trifluoride cation 3 E' 1662 826 -836 2.013
C2Cl2+ dichloroacetylene cation 5 Πu 233 193 -40 1.209
C2Cl2+ dichloroacetylene cation 4 Πg 318 507 189 0.627
FOOF Perfluoroperoxide 1 A 1210 952 -258 1.271
FOOF Perfluoroperoxide 4 A 202 162 -40 1.250
FOOF Perfluoroperoxide 5 B 614 932 318 0.659
NF3 Nitrogen trifluoride 2 A1 647 531 -116 1.219
NF3 Nitrogen trifluoride 4 E 492 392 -100 1.254
FNO Nitrosyl fluoride 1 A' 1844 1503 -341 1.227
NO2 Nitrogen dioxide 3 B2 1618 1316 -302 1.230
BrF5 bromine pentafluoride 6 B2 281 211 -70 1.333
BeF2 Beryllium fluoride 3 Πu 343 255 -88 1.343
CaF2 Calcium difluoride 2 A1 120 17 -103 7.151
ClF3 Chlorine trifluoride 6 B2 442 362 -80 1.220
O3 Ozone 2 A1 705 560 -145 1.259
PCl5 Phosphorus pentachloride 2 A1' 370 260 -110 1.424
N2O3 Dinitrogen trioxide 9 A" 63 153 90 0.413
Cu2 Copper dimer 1 Σg 265 213 -52 1.243
Li2O dilithium oxide 3 Πu 112 75 -37 1.496
CaOH Calcium monohydroxide 2 Σ 353 631 278 0.559
CaOH Calcium monohydroxide 3 Π 609 475 -134 1.282
DO Hydroxyl-d 1 Σ 2720 2313 -407 1.176
C3 carbon trimer 3 Πu 63 159 96 0.398
C3 carbon trimer 3 Πu 63 159 96 0.398
C3 carbon trimer 3 Πu 63 159 96 0.398
C3 carbon trimer 3 Πu 63 159 96 0.398
N2O4 Dinitrogen tetroxide 9 B2u 265 196 -69 1.349
NH2- amino anion 1 A1 3122 2582 -540 1.209
NH2- amino anion 3 B2 3190 2621 -569 1.217
SiH- silicon monohydride anion 1 Σ 2175 1784 -391 1.219
SiH- silicon monohydride anion 1 Σ 2175 1784 -391 1.219
SiH- silicon monohydride anion 1 Σ 2175 1784 -391 1.219
SiH- silicon monohydride anion 1 Σ 2175 1784 -391 1.219
ND3 Ammonia-d3 2 A1 748 524 -224 1.427
NH Imidogen 1 Σ 3283 2836 -447 1.157
N2F2 Dinitrogen difluoride, (E)- 1 Ag 1523 1262 -261 1.207
DF Hydrofluoric acid-d 1 Σ 2998 2569 -429 1.167
SF5Cl sulfur chloropentafluoride 5 B1 625 453 -172 1.380
SF5Cl sulfur chloropentafluoride 7 B2 505 307 -198 1.644
SF5Cl sulfur chloropentafluoride 11 E 397 240 -157 1.651
FO2 Dioxygen monofluoride 1 A' 1487 1078 -409 1.379
ClOO chloroperoxy radical 1 A' 1443 1049 -394 1.376
ClOO chloroperoxy radical 3 A' 201 290 88 0.695
H3O+ hydronium 2 A1 954 474 -480 2.012
GeH2 germylene 1 A1 1856 888 -968 2.091
GeH2 germylene 2 A1 916 1795 879 0.510
ClONO2 Chlorine nitrate 7 A' 273 225 -48 1.213
Mg2 Magnesium diatomic 1 Σg 51 112 61 0.455
Mg2 Magnesium diatomic 1 Σg 51 112 61 0.455
Mg2 Magnesium diatomic 1 Σg 51 112 61 0.455
Mg2 Magnesium diatomic 1 Σg 51 112 61 0.455
ClS2 Sulfur chloride 1 A' 662 464 -198 1.426
H2OH2O water dimer 3 A' 3601 3146 -455 1.144
H2OH2O water dimer 6 A' 311 539 228 0.577
H2OH2O water dimer 7 A' 143 287 144 0.498
H2OH2O water dimer 8 A' 103 207 104 0.497
H2OH2O water dimer 10 A" 523 871 348 0.600
H2OH2O water dimer 11 A" 108 224 116 0.482
Na2 Sodium diatomic 1 Σg 159 81 -78 1.955
H2POH Phosphinous acid 9 A" 375 225 -151 1.671
ZnCH3 Zinc monomethyl 6 E 315 630 315 0.500
ONONO Nitrosyl nitrite 6 B1 140 113 -27 1.240
ONONO Nitrosyl nitrite 9 B2 380 601 221 0.632