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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
CH3COOH Acetic acid 18 A" 93 66 -27 1.412
CH3OH Methyl alcohol 12 A" 200 303 103 0.660
C2H6O2S Dimethyl sulfone 20 B1 262 211 -51 1.243
CH3NH2 methyl amine 14 A" 1195 932 -263 1.283
CH3COCl Acetyl Chloride 15 A" 166 125 -41 1.331
CBr2F2 Methane, dibromodifluoro- 3 A1 140 330 190 0.424
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
C3H6O 2-Propen-1-ol 21 A 554 428 -126 1.294
C4H8O Furan, tetrahydro- 33 B 137 54 -83 2.522
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 157 -36 1.229
C4H6O2 2,3-Butanedione 13 Au 1111 912 -199 1.218
C4H6O2 2,3-Butanedione 21 Bg 240 99 -141 2.427
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.222
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
C3O2 Carbon suboxide 7 Πu 61 156 95 0.392
C5H8 1,4-Pentadiene 31 B 721 588 -133 1.227
C5H8 1,4-Pentadiene 33 B 331 98 -233 3.377
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C6H10 1,5-Hexadiene 29 Bg 264 183 -81 1.446
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.384
COBr2 Carbonic dibromide 6 B2 512 346 -166 1.480
COBr2 Carbonic dibromide 4 B1 757 524 -233 1.445
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 188 -39 1.209
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.215
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 206 62 0.699
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 135 -36 1.263
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.327
C5H8 1,3-Pentadiene, (E)- 32 A" 129 200 71 0.645
C5H8 1,3-Pentadiene, (E)- 31 A" 361 247 -114 1.463
CH3 Methyl radical 2 A2" 606 499 -107 1.215
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 97 -261 3.679
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
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.272
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
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
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
GeH2 germylene 2 A1 916 1953 1037 0.469
GeH2 germylene 1 A1 1856 909 -947 2.041
Mg2 Magnesium diatomic 1 Σg 51 86 35 0.597
ZnCH3 Zinc monomethyl 6 E 315 585 270 0.538
C2F6 hexafluoroethane 4 A1u 68 56 -12 1.210
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.208
C2H3NO3 Oxamic acid 16 A" 984 796 -188 1.236
C2H3NO3 Oxamic acid 18 A" 745 603 -142 1.236
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 325 144 0.557
C3 carbon trimer 3 Πu 63 151 87 0.421
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.509
C6H12 2-Butene, 2,3-dimethyl- 12 Au 182 148 -34 1.227
C3H8O2S (Methylsulphonyl)ethane 33 ?a 257 214 -43 1.203
C3H6O2 1,3-Dioxolane 6 A 1361 2838 1477 0.480
C3H6O2 1,3-Dioxolane 13 A 658 1222 564 0.539
NaOH sodium hydroxide 3 Π 300 246 -54 1.220
C5H8 Cyclopentene 18 A' 254 146 -108 1.739
C2H3NO3 Oxamic acid 3 A' 2600 3462 862 0.751
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.281
C2H3NO3 Oxamic acid 17 A" 815 646 -169 1.261
C3H6O2 1,3-Dioxolane 4 A 1509 2928 1419 0.515
C3H7N Cyclopropylamine 12 A' 989 808 -181 1.224
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.306
BF3+ boron trifluoride cation 4 E' 411 -211 -622 -1.945
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.645
C5H12 Pentane 23 A2 131 107 -24 1.226
C3H8O2S (Methylsulphonyl)ethane 32 ?a 324 267 -57 1.212
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.216
C3H6O2 1,3-Dioxolane 5 A 1480 2895 1415 0.511
BF3+ boron trifluoride cation 3 E' 1662 891 -770 1.865