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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 mPW1PW91/6-31G**
Calculated values were scaled by 0.9515.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.645
CH3CONH2 Acetamide 20 A 259 152 -107 1.700
CH3COOH Acetic acid 18 A" 93 76 -17 1.230
CH3OH Methyl alcohol 12 A" 200 322 122 0.621
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3OH Methyl alcohol 12 A" 200 322 122 0.621
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3COCH3 Acetone 12 A2 77 32 -45 2.393
C2H6O2S Dimethyl sulfone 13 A2 326 271 -55 1.205
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.252
CHONH2 formamide 12 A" 289 197 -92 1.468
CH3COCl Acetyl Chloride 15 A" 166 132 -34 1.253
CBr2F2 Methane, dibromodifluoro- 3 A1 140 324 184 0.433
C2F6 hexafluoroethane 4 A1u 68 47 -21 1.451
C3F8 perfluoropropane 13 A2 276 207 -69 1.331
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.208
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 62 -13 1.207
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.191
C3H6O 2-Propen-1-ol 22 A 377 312 -65 1.209
C3H6O 2-Propen-1-ol 24 A 188 112 -77 1.686
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.201
C5H8 Cyclopentene 18 A' 254 140 -114 1.812
C8H8 cubane 15 T2g 821 651 -170 1.262
C8H8 cubane 17 T2u 1036 825 -211 1.255
C2H4O3 trioxolane124 21 B 193 158 -35 1.225
C4H6O2 2,3-Butanedione 9 Ag 614 506 -108 1.214
C4H6O2 2,3-Butanedione 13 Au 1111 913 -198 1.217
C4H6O2 2,3-Butanedione 21 Bg 240 94 -146 2.546
C6H4 Benzyne 24 B2 472 377 -95 1.251
C5H12 Propane, 2,2-dimethyl- 12 T1 203 302 99 0.673
C2H3NO3 Oxamic acid 3 A' 2600 3471 871 0.749
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.275
C2H3NO3 Oxamic acid 16 A" 984 790 -194 1.245
C2H3NO3 Oxamic acid 17 A" 815 657 -158 1.240
C2H3NO3 Oxamic acid 18 A" 745 612 -133 1.218
C2H3NO3 Oxamic acid 21 A" 162 69 -93 2.363
C3H6O Oxetane 12 A2 986 807 -179 1.222
C3H6O Oxetane 18 B1 90 50 -40 1.787
C3O2 Carbon suboxide 7 Πu 61 114 53 0.535
C5H8 1,4-Pentadiene 16 A 137 283 146 0.485
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.229
C6H10 1,5-Hexadiene 14 Ag 351 255 -96 1.378
C6H10 1,5-Hexadiene 29 Bg 264 185 -79 1.425
COBr2 Carbonic dibromide 4 B1 757 506 -251 1.496
COBr2 Carbonic dibromide 6 B2 512 335 -177 1.528
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.215
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.217
CH2D2 methane-d2 6 B1 3013 2256 -757 1.336
CH2D2 methane-d2 8 B2 2234 3045 811 0.734
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.213
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.696
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.697
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.696
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.697
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.329
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.329
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 141 -30 1.216
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 138 -33 1.235
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 141 -30 1.216
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 138 -33 1.235
CH3OO methylperoxy radical 12 A" 170 128 -42 1.328
CH3 Methyl radical 2 A2" 606 445 -161 1.363
CH3 Methyl radical 2 A2" 606 445 -161 1.363
CH3 Methyl radical 2 A2" 606 445 -161 1.363
CH3 Methyl radical 2 A2" 606 445 -161 1.363
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 864 -272 1.315
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 147 -117 1.795
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 99 -259 3.602
CH2OH Hydroxymethyl radical 9 A 234 413 179 0.567
BF3+ boron trifluoride cation 3 E' 1662 903 -758 1.839
BF3+ boron trifluoride cation 4 E' 411 -194 -605 -2.123
C4H6 Methylenecyclopropane 17 B1 360 284 -76 1.270
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.306
HClO4 perchloric acid 12 A" 191 153 -38 1.249
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.240
BrF5 bromine pentafluoride 6 B2 281 212 -69 1.325
SF4 Sulfur tetrafluoride 4 A1 228 186 -42 1.228
ZnCN Zinc monocyanide 3 Π 212 68 -144 3.134
AsH3+ Arsine cation 2 A1 452 666 214 0.679
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.450
PCl5 Phosphorus pentachloride 2 A1' 370 270 -100 1.371
C3 carbon trimer 3 Πu 63 142 78 0.447
CaOH Calcium monohydroxide 2 Σ 353 600 247 0.588
CaOH Calcium monohydroxide 3 Π 609 342 -267 1.781
SiH- silicon monohydride anion 1 Σ 2175 1759 -416 1.236
SiH- silicon monohydride anion 1 Σ 2175 1759 -416 1.236
SF5Cl sulfur chloropentafluoride 5 B1 625 448 -177 1.397
SF5Cl sulfur chloropentafluoride 7 B2 505 303 -202 1.666
SF5Cl sulfur chloropentafluoride 11 E 397 239 -158 1.664
H3O+ hydronium 2 A1 954 754 -200 1.265
ZnH2 Zinc hydride 3 Πu 633 479 -153 1.320
SiH- silicon monohydride anion 1 Σ 2175 1759 -416 1.236
SiH- silicon monohydride anion 1 Σ 2175 1759 -416 1.236
H2POH Phosphinous acid 9 A" 375 254 -122 1.479
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.595
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.595
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.595
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.595
ZnCH3 Zinc monomethyl 6 E 315 595 280 0.529
ClOO chloroperoxy radical 2 A' 414 278 -136 1.488
ClOO chloroperoxy radical 3 A' 201 121 -80 1.661
Cl3- trichloride anion 2 Σu 327 267 -60 1.223
GeH2 germylene 1 A1 1856 910 -946 2.040
GeH2 germylene 2 A1 916 1956 1040 0.468
H2OH2O water dimer 7 A' 143 211 68 0.679
H2OH2O water dimer 8 A' 103 148 45 0.694
H2OH2O water dimer 11 A" 108 168 60 0.644