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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
CH3CONH2 Acetamide 20 A 259 397 139 0.651
CH3COOH Acetic acid 11 A' 657 542 -115 1.211
CH3OH Methyl alcohol 12 A" 200 359 159 0.558
CH3COCH3 Acetone 12 A2 77 61 -16 1.267
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.217
CH3NH2 methyl amine 14 A" 1195 947 -248 1.262
CHONH2 formamide 12 A" 289 495 206 0.584
CBr2F2 Methane, dibromodifluoro- 3 A1 140 326 186 0.430
C3H6O 2-Propen-1-ol 22 A 377 297 -81 1.272
C3H6O 2-Propen-1-ol 24 A 188 98 -90 1.914
C3H6O 2-Propen-1-ol 21 A 554 442 -112 1.254
CH3OCHO methyl formate 18 A" 130 76 -54 1.711
C4H8O Furan, tetrahydro- 33 B 137 59 -78 2.331
N2H4 Hydrazine 12 B 966 791 -175 1.222
N2H4 Hydrazine 6 A 780 603 -177 1.293
C4H6O2 2,3-Butanedione 21 Bg 240 61 -179 3.955
C4H6O2 2,3-Butanedione 16 Au 48 36 -12 1.332
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
C3H6O Oxetane 7 A1 1018 841 -177 1.211
C3O2 Carbon suboxide 7 Πu 61 145 84 0.420
HCNO fulminic acid 5 Π 224 528 304 0.425
Zn(CH3)2 dimethyl zinc 11 E' 134 -100 -234 -1.340
C5H8 1,4-Pentadiene 31 B 721 592 -129 1.218
C5H8 1,4-Pentadiene 33 B 331 90 -241 3.660
C5H8 1,4-Pentadiene 17 A 102 77 -25 1.316
C5H8 1,4-Pentadiene 16 A 137 298 161 0.459
C6H10 1,5-Hexadiene 29 Bg 264 170 -94 1.555
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.349
COBr2 Carbonic dibromide 6 B2 512 338 -174 1.515
COBr2 Carbonic dibromide 4 B1 757 523 -234 1.448
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.212
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)- 32 A" 171 137 -34 1.244
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.332
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
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)- 11 A1 1136 863 -273 1.317
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 142 -122 1.864
OH Hydroxyl radical 1 Σ 3738 3177 -561 1.177
OH+ hydoxyl cation 1 Σ 3113 2596 -517 1.199
C2Cl2 dichloroacetylene 4 Πg 333 499 166 0.667
HF Hydrogen fluoride 1 Σ 4138 3544 -594 1.168
NH3 Ammonia 2 A1 950 691 -259 1.375
H2SO4 Sulfuric acid 15 B 288 231 -56 1.244
H2SO4 Sulfuric acid 8 A 224 179 -45 1.251
HNO3 Nitric acid 7 A' 579 482 -97 1.201
NF3 Nitrogen trifluoride 2 A1 647 531 -116 1.219
NF3 Nitrogen trifluoride 4 E 492 392 -100 1.254
AsH3+ Arsine cation 2 A1 452 685 233 0.660
FNO Nitrosyl fluoride 1 A' 1844 1503 -341 1.227
BrF5 bromine pentafluoride 6 B2 281 211 -70 1.333
CaF2 Calcium difluoride 2 A1 120 17 -103 7.151
ClF3 Chlorine trifluoride 6 B2 442 362 -80 1.220
PCl5 Phosphorus pentachloride 2 A1' 370 260 -110 1.424
O3 Ozone 2 A1 705 560 -145 1.259
NO2 Nitrogen dioxide 3 B2 1618 1316 -302 1.230
N2O3 Dinitrogen trioxide 9 A" 63 153 90 0.413
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
Cu2 Copper dimer 1 Σg 265 213 -52 1.243
ND3 Ammonia-d3 2 A1 748 524 -224 1.427
DO Hydroxyl-d 1 Σ 2720 2313 -407 1.176
NH2- amino anion 3 B2 3190 2621 -569 1.217
NH2- amino anion 1 A1 3122 2582 -540 1.209
NH Imidogen 1 Σ 3283 2836 -447 1.157
SiH- silicon monohydride anion 1 Σ 2175 1784 -391 1.219
N2F2 Dinitrogen difluoride, (E)- 1 Ag 1523 1262 -261 1.207
H3O+ hydronium 2 A1 954 474 -480 2.012
DF Hydrofluoric acid-d 1 Σ 2998 2569 -429 1.167
ClONO2 Chlorine nitrate 7 A' 273 225 -48 1.213
FO2 Dioxygen monofluoride 1 A' 1487 1078 -409 1.379
ClOO chloroperoxy radical 3 A' 201 290 88 0.695
ClOO chloroperoxy radical 1 A' 1443 1049 -394 1.376
GeH2 germylene 2 A1 916 1795 879 0.510
GeH2 germylene 1 A1 1856 888 -968 2.091
Na2 Sodium diatomic 1 Σg 159 81 -78 1.955
Mg2 Magnesium diatomic 1 Σg 51 112 61 0.455
ZnCH3 Zinc monomethyl 6 E 315 630 315 0.500
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.220
C4H8O2 1,4-Dioxane 19 Au 288 220 -68 1.311
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 332 151 0.544
O2+ diatomic oxygen cation 1 Σg 1906 1440 -466 1.324
C3 carbon trimer 3 Πu 63 159 96 0.398
ClS2 Sulfur chloride 1 A' 662 464 -198 1.426
C2H4O3 trioxolane124 21 B 193 160 -33 1.206
C2H3NO3 Oxamic acid 21 A" 162 113 -49 1.427
C3H6O2 1,3-Dioxolane 6 A 1361 2910 1549 0.468
C3H6O2 1,3-Dioxolane 13 A 658 1195 537 0.551
C3H7N Cyclopropylamine 14 A' 762 623 -139 1.222
HNCO Isocyanic acid 5 A' 577 427 -150 1.352
C2H2O2 Ethanedial 7 Au 127 194 67 0.656
C5H8 Cyclopentene 18 A' 254 126 -128 2.014
OH- hydroxide anion 1 Σ 3738 2667 -1072 1.402
NF2 Difluoroamino radical 2 A1 573 460 -113 1.246
C2Cl2+ dichloroacetylene cation 4 Πg 318 507 189 0.627
N2O4 Dinitrogen tetroxide 9 B2u 265 196 -69 1.349
C2Cl2+ dichloroacetylene cation 5 Πu 233 193 -40 1.209
BF3+ boron trifluoride cation 4 E' 411 -221 -632 -1.860
C2H3NO3 Oxamic acid 3 A' 2600 3381 781 0.769
C2H3NO3 Oxamic acid 15 A' 328 253 -75 1.297
C2H3NO3 Oxamic acid 17 A" 815 665 -150 1.225
C3H6O2 1,3-Dioxolane 4 A 1509 2925 1416 0.516
C3H7N Cyclopropylamine 12 A' 989 786 -203 1.258
CH2OH Hydroxymethyl radical 9 A 234 399 165 0.587
BF3+ boron trifluoride cation 3 E' 1662 826 -836 2.013
C3H6O2 1,3-Dioxolane 5 A 1480 2919 1439 0.507
HNCO Isocyanic acid 4 A' 777 574 -202 1.352