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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
CH3CONH2 Acetamide 20 A 259 392 133 0.660
CH3COOH Acetic acid 18 A" 93 75 -18 1.243
CH3OH Methyl alcohol 12 A" 200 346 146 0.579
CH3OH Methyl alcohol 12 A" 200 346 146 0.578
CH3OH Methyl alcohol 12 A" 200 346 146 0.579
CH3OH Methyl alcohol 12 A" 200 346 146 0.578
C2H2 Acetylene 4 Πg 612 408 -204 1.502
CH3CCH propyne 10 E 328 255 -73 1.285
C3F8 perfluoropropane 13 A2 276 222 -54 1.242
CBr2F2 Methane, dibromodifluoro- 3 A1 140 332 192 0.422
CH3COOCH3 methyl acetate 27 A" 110 55 -55 1.987
C6H4O2 parabenzoquinone 17 B2g 241 173 -68 1.390
C6H4O2 parabenzoquinone 30 B3u 109 82 -27 1.325
C9H8 Indene 40 A" 690 537 -153 1.285
C6H5CN phenyl cyanide 19 B1 688 565 -123 1.219
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.746
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
CH2NN diazomethane 6 B1 406 333 -73 1.220
NH2CN cyanamide 5 A' 408 682 274 0.598
C4H6O2 2,3-Butanedione 21 Bg 240 121 -119 1.981
C6H5F Fluorobenzene 18 B1 685 552 -133 1.241
CH3CCCH3 2-Butyne 16 E" 371 229 -142 1.617
C3H6O Oxetane 12 A2 986 818 -168 1.205
C3H6O Oxetane 18 B1 90 39 -51 2.309
HCNO fulminic acid 5 Π 224 102 -122 2.194
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.234
C5H8 1,4-Pentadiene 16 A 137 291 154 0.472
COBr2 Carbonic dibromide 4 B1 757 501 -256 1.512
COBr2 Carbonic dibromide 6 B2 512 343 -169 1.494
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.227
C6H8 1,4-Cyclohexadiene 23 B2g 403 335 -68 1.203
C6H8 1,4-Cyclohexadiene 19 B1u 108 85 -23 1.266
CH2D2 methane-d2 6 B1 3013 2235 -778 1.348
CH2D2 methane-d2 8 B2 2234 3017 783 0.740
ZnS Zinc sulfide 1 Σ 459 345 -114 1.331
NaOH sodium hydroxide 3 Π 300 202 -98 1.486
LiOH lithium hydroxide 3 Π 257 389 132 0.660
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.670
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.669
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.670
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 215 71 0.669
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.377
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.378
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.377
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 331 -125 1.378
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 104 -67 1.644
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 105 -66 1.636
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 104 -67 1.644
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 105 -66 1.636
CH3 Methyl radical 2 A2" 606 427 -179 1.419
CH3 Methyl radical 2 A2" 606 427 -179 1.419
CH3 Methyl radical 2 A2" 606 427 -179 1.419
CH3 Methyl radical 2 A2" 606 427 -179 1.419
C2H5 Ethyl radical 9 A' 528 431 -97 1.224
CH2OH Hydroxymethyl radical 8 A 482 690 208 0.698
CH2OH Hydroxymethyl radical 9 A 234 451 217 0.519
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.348
C3H3 Propargyl radical 7 B1 490 400 -90 1.226
OH- hydroxide anion 1 Σ 3738 3305 -433 1.131
C2Cl2 dichloroacetylene 4 Πg 333 153 -180 2.177
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.321
BF3+ boron trifluoride cation 3 E' 1662 597 -1064 2.781
BF3+ boron trifluoride cation 4 E' 411 -1028 -1439 -0.400
MgF2 Magnesium fluoride 3 Πu 165 137 -28 1.205
FOOF Perfluoroperoxide 1 A 1210 992 -218 1.220
AsH3+ Arsine cation 2 A1 452 652 200 0.693
ZnCl Zinc monochloride 1 Σ 391 299 -92 1.307
CaF2 Calcium difluoride 2 A1 120 55 -65 2.175
N2O3 Dinitrogen trioxide 9 A" 63 137 74 0.458
CaOH Calcium monohydroxide 2 Σ 353 627 274 0.563
CaOH Calcium monohydroxide 3 Π 609 366 -243 1.666
C4 Carbon tetramer 4 Πg 323 249 -74 1.298
S3- Sulfur trimer anion 3 B2 594 477 -118 1.247
Li2O dilithium oxide 3 Πu 112 55 -56 2.018
C3 carbon trimer 3 Πu 63 34 -30 1.871
C3 carbon trimer 3 Πu 63 39 -25 1.643
C3 carbon trimer 3 Πu 63 34 -30 1.871
C3 carbon trimer 3 Πu 63 39 -25 1.643
SF5Cl sulfur chloropentafluoride 11 E 397 248 -149 1.602
ZnH Zinc monohydride 1 Σ 1608 1105 -502 1.454
SiH- silicon monohydride anion 1 Σ 2175 1675 -500 1.298
SiH- silicon monohydride anion 1 Σ 2175 1675 -500 1.298
SiH- silicon monohydride anion 1 Σ 2175 1675 -500 1.298
SiH- silicon monohydride anion 1 Σ 2175 1675 -500 1.298
SF5Cl sulfur chloropentafluoride 5 B1 625 466 -159 1.342
SF5Cl sulfur chloropentafluoride 7 B2 505 317 -188 1.594
H3O+ hydronium 2 A1 954 775 -179 1.231
H2OH2O water dimer 11 A" 108 163 55 0.661
Cl3- trichloride anion 2 Σu 327 186 -141 1.755
GeH2 germylene 1 A1 1856 894 -962 2.075
GeH2 germylene 2 A1 916 1767 851 0.518
H2POH Phosphinous acid 9 A" 375 263 -113 1.429
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.539
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.539
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.539
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.539
ZnCH3 Zinc monomethyl 6 E 315 614 299 0.513