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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 QCISD/6-311G*
Calculated values were scaled by 0.9574.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 18 A" 93 75 -18 1.243
C2H2 Acetylene 4 Πg 612 408 -204 1.502
CH3COOCH3 methyl acetate 27 A" 110 55 -55 1.987
C6H4O2 parabenzoquinone 30 B3u 109 82 -27 1.325
C3H6O 2-Propen-1-ol 21 A 554 433 -121 1.279
C6H5Cl chlorobenzene 18 B1 685 490 -194 1.396
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 147 -46 1.313
C5H8 Cyclopentene 18 A' 254 164 -90 1.551
C6H5F Fluorobenzene 18 B1 685 552 -133 1.241
C3H6O Oxetane 18 B1 90 39 -51 2.309
C5H8 1,4-Pentadiene 16 A 137 291 154 0.472
C3H6O2 1,3-Dioxolane 6 A 1361 2842 1481 0.479
C3H6O2 1,3-Dioxolane 13 A 658 1246 588 0.528
NaOH sodium hydroxide 3 Π 300 202 -98 1.486
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 104 -67 1.644
C2H5 Ethyl radical 9 A' 528 431 -97 1.224
OH- hydroxide anion 1 Σ 3738 3305 -433 1.131
C2Cl2 dichloroacetylene 4 Πg 333 153 -180 2.177
AsH3+ Arsine cation 2 A1 452 652 200 0.693
Li2O dilithium oxide 3 Πu 112 55 -56 2.018
CaOH Calcium monohydroxide 3 Π 609 366 -243 1.666
S3- Sulfur trimer anion 3 B2 594 477 -118 1.247
ZnH Zinc monohydride 1 Σ 1608 1105 -502 1.454
CH2NN diazomethane 6 B1 406 333 -73 1.220
NH2CN cyanamide 5 A' 408 682 274 0.598
C3 carbon trimer 3 Πu 63 34 -30 1.871
CaOH Calcium monohydroxide 2 Σ 353 627 274 0.563
C4 Carbon tetramer 4 Πg 323 249 -74 1.298
H3O+ hydronium 2 A1 954 775 -179 1.231
GeH2 germylene 1 A1 1856 894 -962 2.075
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.539
ZnCH3 Zinc monomethyl 6 E 315 614 299 0.513
COBr2 Carbonic dibromide 6 B2 512 343 -169 1.494
ZnS Zinc sulfide 1 Σ 459 345 -114 1.331
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.670
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.377
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.348
GeH2 germylene 2 A1 916 1767 851 0.518
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.234
COBr2 Carbonic dibromide 4 B1 757 501 -256 1.512
C3H6O2 1,3-Dioxolane 4 A 1509 2921 1412 0.517
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.321
BF3+ boron trifluoride cation 4 E' 411 -1028 -1439 -0.400
ZnCl Zinc monochloride 1 Σ 391 299 -92 1.307
CH3OH Methyl alcohol 12 A" 200 346 146 0.579
CH3NH2 methyl amine 14 A" 1195 951 -244 1.256
C6H4O2 parabenzoquinone 17 B2g 241 173 -68 1.390
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.746
C4H6O2 2,3-Butanedione 21 Bg 240 121 -119 1.981
CH3CCCH3 2-Butyne 16 E" 371 229 -142 1.617
C3H6O Oxetane 12 A2 986 818 -168 1.205
SiH- silicon monohydride anion 1 Σ 2175 1675 -500 1.298
C5H8 1,4-Pentadiene 31 B 721 579 -142 1.245
C5H8 1,4-Pentadiene 33 B 331 92 -239 3.610
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.227
C6H8 1,4-Cyclohexadiene 19 B1u 108 85 -23 1.266
C6H8 1,4-Cyclohexadiene 23 B2g 403 335 -68 1.203
C3H6O2 1,3-Dioxolane 5 A 1480 2896 1416 0.511
LiOH lithium hydroxide 3 Π 257 389 132 0.660
CH3 Methyl radical 2 A2" 606 427 -179 1.419
C3H3 Propargyl radical 7 B1 490 400 -90 1.226
BF3+ boron trifluoride cation 3 E' 1662 597 -1064 2.781
CaF2 Calcium difluoride 2 A1 120 55 -65 2.175
N2O3 Dinitrogen trioxide 9 A" 63 137 74 0.458
CH3CONH2 Acetamide 20 A 259 392 133 0.660
CH3CCH propyne 10 E 328 255 -73 1.285
CBr2F2 Methane, dibromodifluoro- 3 A1 140 332 192 0.422
C6H5CN phenyl cyanide 19 B1 688 565 -123 1.219
HCNO fulminic acid 5 Π 224 102 -122 2.194