return to home page

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 B3PW91/3-21G*
Calculated values were scaled by 0.9594.

Species Name mode Symmetry Experiment Theory difference ratio
NH2CONH2 Urea 9 A2 233 131 -102 1.775
NH2CONH2 Urea 16 B2 1393 3564 2171 0.391
NH2CONH2 Urea 17 B2 1004 3434 2430 0.292
NH2CONH2 Urea 18 B2 543 968 425 0.561
CH3CONH2 Acetamide 20 A 259 400 141 0.648
CH3COOH Acetic acid 11 A' 657 544 -113 1.209
CH3OH Methyl alcohol 12 A" 200 369 169 0.541
CH3COCH3 Acetone 12 A2 77 61 -16 1.260
C2H6O2S Dimethyl sulfone 13 A2 326 267 -59 1.219
CH3NH2 methyl amine 14 A" 1195 952 -243 1.255
CHONH2 formamide 12 A" 289 496 207 0.582
HNCO Isocyanic acid 5 A' 577 445 -132 1.298
HNCO Isocyanic acid 4 A' 777 575 -201 1.350
CBr2F2 Methane, dibromodifluoro- 3 A1 140 324 184 0.432
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 519 -113 1.217
CH3COOCH3 methyl acetate 26 A" 136 73 -63 1.869
CH3COOCH3 methyl acetate 27 A" 110 62 -48 1.788
C3H6O 2-Propen-1-ol 22 A 377 298 -79 1.264
C3H6O 2-Propen-1-ol 24 A 188 100 -88 1.883
C3H6O 2-Propen-1-ol 21 A 554 443 -111 1.251
C2H2O2 Ethanedial 7 Au 127 195 68 0.651
CH3OCHO methyl formate 18 A" 130 73 -57 1.778
C4H8O Furan, tetrahydro- 33 B 137 54 -83 2.529
C4H9N Pyrrolidine 36 A" 65 29 -36 2.241
C4H8O2 1,4-Dioxane 19 Au 288 221 -67 1.306
C5H8 Cyclopentene 18 A' 254 125 -129 2.030
CH2N4 1H-Tetrazole 11 A' 925 763 -162 1.212
C2H4O3 trioxolane124 21 B 193 159 -34 1.214
N2H4 Hydrazine 12 B 966 800 -166 1.208
N2H4 Hydrazine 6 A 780 601 -179 1.298
C4H6O2 2,3-Butanedione 21 Bg 240 59 -181 4.064
C4H6O2 2,3-Butanedione 16 Au 48 35 -13 1.391
C2N2 Cyanogen 4 Πg 503 760 257 0.662
C5H12 Propane, 2,2-dimethyl- 12 T1 203 320 117 0.635
C2H3NO3 Oxamic acid 15 A' 328 253 -75 1.295
C2H3NO3 Oxamic acid 17 A" 815 666 -149 1.223
C2H3NO3 Oxamic acid 21 A" 162 114 -48 1.424
C2H3NO3 Oxamic acid 3 A' 2600 3380 780 0.769
C3H6O Oxetane 23 B2 1228 949 -279 1.294
C3H6O Oxetane 7 A1 1018 839 -179 1.214
C3O2 Carbon suboxide 7 Πu 61 146 85 0.417
HCNO fulminic acid 5 Π 224 529 305 0.424
Zn(CH3)2 dimethyl zinc 11 E' 134 -104 -238 -1.285
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 334 153 0.541
C5H8 1,4-Pentadiene 31 B 721 594 -127 1.215
C5H8 1,4-Pentadiene 33 B 331 92 -239 3.596
C5H8 1,4-Pentadiene 17 A 102 79 -23 1.289
C5H8 1,4-Pentadiene 16 A 137 300 163 0.457
C6H10 1,5-Hexadiene 29 Bg 264 176 -88 1.503
C6H10 1,5-Hexadiene 14 Ag 351 263 -88 1.333
COBr2 Carbonic dibromide 6 B2 512 336 -176 1.523
COBr2 Carbonic dibromide 4 B1 757 523 -234 1.446
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 188 -39 1.208
CH3ONO Methyl nitrite 15 A" 186 135 -51 1.374
C3H7N Cyclopropylamine 12 A' 989 788 -201 1.255
C3H7N Cyclopropylamine 14 A' 762 621 -141 1.227
C4N2 2-Butynedinitrile 6 Πg 504 909 405 0.554
C4N2 2-Butynedinitrile 8 Πu 472 687 215 0.687
LiOH lithium hydroxide 3 Π 257 399 142 0.643
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 139 -32 1.232
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.329
CCl2 dichloromethylene 3 B2 758 601 -157 1.261
C5H8 1,3-Pentadiene, (E)- 32 A" 129 195 66 0.660
C5H8 1,3-Pentadiene, (E)- 31 A" 361 246 -115 1.467
C2H Ethynyl radical 3 Π 372 538 167 0.690
CH3 Methyl radical 2 A2" 606 472 -134 1.284
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 97 -261 3.690
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 866 -270 1.311
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 143 -121 1.840
OH- hydroxide anion 1 Σ 3738 2657 -1081 1.407
OH Hydroxyl radical 1 Σ 3738 3175 -563 1.177
OH+ hydoxyl cation 1 Σ 3113 2601 -513 1.197
NF2 Difluoroamino radical 2 A1 573 457 -116 1.254
C2Cl2 dichloroacetylene 4 Πg 333 493 160 0.675
C2Cl2+ dichloroacetylene cation 4 Πg 318 508 190 0.625
C2Cl2+ dichloroacetylene cation 5 Πu 233 193 -40 1.208
BF3+ boron trifluoride cation 3 E' 1662 925 -736 1.796
BF3+ boron trifluoride cation 4 E' 411 76 -335 5.426
HF Hydrogen fluoride 1 Σ 4138 3544 -594 1.168
NH3 Ammonia 2 A1 950 689 -261 1.378
H2SO4 Sulfuric acid 15 B 288 233 -55 1.237
H2SO4 Sulfuric acid 8 A 224 179 -45 1.250
HNO3 Nitric acid 7 A' 579 479 -100 1.209
O2+ diatomic oxygen cation 1 Σg 1906 1422 -483 1.340
NF3 Nitrogen trifluoride 2 A1 647 526 -121 1.231
NF3 Nitrogen trifluoride 4 E 492 388 -104 1.269
AsH3+ Arsine cation 2 A1 452 690 238 0.655
FNO Nitrosyl fluoride 1 A' 1844 1498 -346 1.231
FNO3 Fluorine nitrate 7 A' 303 249 -54 1.218
BrF5 bromine pentafluoride 6 B2 281 205 -76 1.370
CaF2 Calcium difluoride 2 A1 120 28 -92 4.225
ClF3 Chlorine trifluoride 6 B2 442 351 -91 1.258
ClF3 Chlorine trifluoride 3 A1 328 273 -55 1.203
PCl5 Phosphorus pentachloride 2 A1' 370 257 -113 1.440
O3 Ozone 2 A1 705 557 -148 1.265
NO2 Nitrogen dioxide 3 B2 1618 1312 -306 1.234
N2O4 Dinitrogen tetroxide 9 B2u 265 187 -78 1.415
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.418
N2O3 Dinitrogen trioxide 1 A' 1832 1526 -306 1.200
Li2O dilithium oxide 3 Πu 112 67 -44 1.658
CaOH Calcium monohydroxide 2 Σ 353 631 278 0.559
CaOH Calcium monohydroxide 3 Π 609 472 -137 1.291
C4 Carbon tetramer 5 Πu 160 133 -27 1.202
Cu2 Copper dimer 1 Σg 265 219 -46 1.208
ND3 Ammonia-d3 2 A1 748 527 -221 1.420
DO Hydroxyl-d 1 Σ 2720 2311 -409 1.177
NH2- amino anion 3 B2 3190 2613 -578 1.221
NH2- amino anion 1 A1 3122 2573 -549 1.213
NH Imidogen 1 Σ 3283 2829 -453 1.160
SiH- silicon monohydride anion 1 Σ 2175 1784 -391 1.219
N2F2 Dinitrogen difluoride, (E)- 1 Ag 1523 1240 -283 1.229
H3O+ hydronium 2 A1 954 480 -475 1.990
DF Hydrofluoric acid-d 1 Σ 2998 2569 -429 1.167
ClONO2 Chlorine nitrate 7 A' 273 220 -53 1.240
FO2 Dioxygen monofluoride 1 A' 1487 1100 -387 1.352
ClOO chloroperoxy radical 1 A' 1443 1090 -353 1.323
GeH2 germylene 2 A1 916 1794 878 0.511
GeH2 germylene 1 A1 1856 892 -964 2.081
Na2 Sodium diatomic 1 Σg 159 255 96 0.625
Mg2 Magnesium diatomic 1 Σg 51 113 62 0.453
ClS2 Sulfur chloride 2 A' 450 369 -81 1.219
ZnCH3 Zinc monomethyl 6 E 315 635 320 0.496