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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 mPW1PW91/6-31+G**
Calculated values were scaled by 0.9518.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.645
CH3COOH Acetic acid 18 A" 93 66 -27 1.412
CH3OH Methyl alcohol 12 A" 200 303 103 0.660
CH3OH Methyl alcohol 12 A" 200 304 104 0.658
CH3OH Methyl alcohol 12 A" 200 303 103 0.660
CH3OH Methyl alcohol 12 A" 200 304 104 0.658
C2H6O2S Dimethyl sulfone 20 B1 262 211 -51 1.243
CH3COCl Acetyl Chloride 15 A" 166 125 -41 1.331
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CBr2F2 Methane, dibromodifluoro- 3 A1 140 330 190 0.424
C2F6 hexafluoroethane 4 A1u 68 56 -12 1.210
C3F8 perfluoropropane 13 A2 276 211 -65 1.307
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.208
CH3COOCH3 methyl acetate 27 A" 110 33 -77 3.373
C6H4O2 parabenzoquinone 30 B3u 109 87 -21 1.244
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.705
C5H12 Pentane 23 A2 131 107 -24 1.226
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 157 -36 1.229
C5H8 Cyclopentene 18 A' 254 146 -108 1.739
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.222
C4H6O2 2,3-Butanedione 13 Au 1111 912 -199 1.218
C4H6O2 2,3-Butanedione 21 Bg 240 99 -141 2.427
C6H4 Benzyne 24 B2 472 376 -96 1.255
C5H12 Propane, 2,2-dimethyl- 12 T1 203 301 98 0.673
C3H6O Oxetane 12 A2 986 804 -182 1.227
C3H6O Oxetane 18 B1 90 28 -61 3.167
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.281
C2H3NO3 Oxamic acid 16 A" 984 796 -188 1.236
C2H3NO3 Oxamic acid 17 A" 815 646 -169 1.261
C2H3NO3 Oxamic acid 18 A" 745 603 -142 1.236
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.509
C2H3NO3 Oxamic acid 3 A' 2600 3462 862 0.751
C3O2 Carbon suboxide 7 Πu 61 156 95 0.392
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.384
C6H10 1,5-Hexadiene 29 Bg 264 183 -81 1.446
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
COBr2 Carbonic dibromide 4 B1 757 524 -233 1.445
COBr2 Carbonic dibromide 6 B2 512 346 -166 1.480
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 188 -39 1.209
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.216
CH2D2 methane-d2 6 B1 3013 2249 -764 1.340
CH2D2 methane-d2 8 B2 2234 3037 803 0.736
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.215
NaOH sodium hydroxide 3 Π 300 246 -54 1.220
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 206 62 0.699
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 206 62 0.699
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.327
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.329
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.327
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.329
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 135 -36 1.263
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 134 -37 1.280
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 135 -36 1.263
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 134 -37 1.280
CH3OO methylperoxy radical 12 A" 170 130 -40 1.307
CH3 Methyl radical 2 A2" 606 499 -107 1.215
CH3 Methyl radical 2 A2" 606 499 -107 1.215
CH3 Methyl radical 2 A2" 606 499 -107 1.215
CH3 Methyl radical 2 A2" 606 499 -107 1.215
CH2OH Hydroxymethyl radical 9 A 234 401 167 0.583
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 862 -274 1.318
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 140 -124 1.886
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 97 -261 3.679
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.272
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.306
BF3+ boron trifluoride cation 3 E' 1662 891 -770 1.865
BF3+ boron trifluoride cation 4 E' 411 -211 -622 -1.945
AsH3+ Arsine cation 2 A1 452 666 214 0.678
BrF5 bromine pentafluoride 6 B2 281 203 -78 1.384
PCl5 Phosphorus pentachloride 2 A1' 370 267 -103 1.386
N2O3 Dinitrogen trioxide 9 A" 63 131 68 0.482
C3 carbon trimer 3 Πu 63 151 87 0.421
C3 carbon trimer 3 Πu 63 148 85 0.428
C3 carbon trimer 3 Πu 63 151 87 0.421
C3 carbon trimer 3 Πu 63 148 85 0.428
CaOH Calcium monohydroxide 2 Σ 353 558 205 0.632
CaOH Calcium monohydroxide 3 Π 609 393 -216 1.551
SiH- silicon monohydride anion 1 Σ 2175 1776 -399 1.224
SiH- silicon monohydride anion 1 Σ 2175 1776 -399 1.224
SiH- silicon monohydride anion 1 Σ 2175 1776 -399 1.224
SiH- silicon monohydride anion 1 Σ 2175 1776 -399 1.224
SF5Cl sulfur chloropentafluoride 5 B1 625 445 -180 1.405
SF5Cl sulfur chloropentafluoride 7 B2 505 301 -204 1.676
SF5Cl sulfur chloropentafluoride 11 E 397 238 -159 1.666
H3O+ hydronium 2 A1 954 746 -209 1.280
FO2 Dioxygen monofluoride 3 A' 376 229 -147 1.643
ClOO chloroperoxy radical 2 A' 414 266 -147 1.553
ClOO chloroperoxy radical 3 A' 201 111 -90 1.813
Cl3- trichloride anion 2 Σu 327 257 -70 1.274
GeH2 germylene 1 A1 1856 909 -947 2.041
GeH2 germylene 2 A1 916 1953 1037 0.469
H2OH2O water dimer 8 A' 103 165 62 0.625
H2OH2O water dimer 11 A" 108 176 68 0.613
H2OH2O water dimer 12 A" 88 141 53 0.625
F3- trifluoride anion 2 Σu 550 428 -122 1.284
H2POH Phosphinous acid 9 A" 375 257 -119 1.462
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.597
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.597
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.597
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.597
ZnCH3 Zinc monomethyl 6 E 315 585 270 0.538