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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 HF/6-31G(2df,p)
Calculated values were scaled by 0.9055.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 173 60 0.652
CH3CONH2 Acetamide 20 A 259 213 -45 1.213
CH3OH Methyl alcohol 12 A" 200 297 97 0.674
CH3OH Methyl alcohol 12 A" 200 298 98 0.671
CH3OH Methyl alcohol 12 A" 200 297 97 0.674
CH3OH Methyl alcohol 12 A" 200 298 98 0.671
CH3COCH3 Acetone 12 A2 77 58 -19 1.330
C2H6O2S Dimethyl sulfone 20 B1 262 207 -55 1.267
CHONH2 formamide 12 A" 289 99 -190 2.910
CBr2F2 Methane, dibromodifluoro- 3 A1 140 342 202 0.409
C3F8 perfluoropropane 13 A2 276 220 -56 1.252
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 525 -107 1.204
CH3COOCH3 methyl acetate 27 A" 110 85 -25 1.297
C6H4O2 parabenzoquinone 30 B3u 109 89 -20 1.223
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.676
C5H12 Pentane 23 A2 131 103 -28 1.271
C4H8O Furan, tetrahydro- 17 A 286 235 -51 1.216
C4H9N Pyrrolidine 36 A" 65 54 -11 1.204
C4H8O2 1,4-Dioxane 19 Au 288 237 -51 1.214
C5H8 Cyclopentene 18 A' 254 137 -117 1.856
CH3NHCH3 Dimethylamine 24 A" 257 214 -43 1.202
C2H3N3 1H-1,2,4-Triazole 18 A" 640 533 -107 1.202
C2H2N4 sym-tetrazine 18 B3u 254 368 114 0.690
NH2CN cyanamide 5 A' 408 629 221 0.648
C5H12 Propane, 2,2-dimethyl- 3 A1 733 2872 2139 0.255
C5H12 Propane, 2,2-dimethyl- 6 E 1451 2918 1467 0.497
C5H12 Propane, 2,2-dimethyl- 7 E 999 1455 456 0.686
C5H12 Propane, 2,2-dimethyl- 8 E 335 1068 733 0.314
C5H12 Propane, 2,2-dimethyl- 10 T1 1461 2916 1455 0.501
C5H12 Propane, 2,2-dimethyl- 11 T1 932 1450 518 0.643
C2H3NO3 Oxamic acid 3 A' 2600 3482 882 0.747
C6H4 Benzyne 24 B2 472 235 -237 2.011
C4H6O2 2,3-Butanedione 21 Bg 240 129 -111 1.857
C2H3NO3 Oxamic acid 15 A' 328 266 -62 1.234
C2H3NO3 Oxamic acid 17 A" 815 645 -170 1.264
C2H3NO3 Oxamic acid 18 A" 745 589 -156 1.265
C2H3NO3 Oxamic acid 21 A" 162 53 -109 3.054
C3H6O Oxetane 12 A2 986 807 -179 1.222
Zn(CH3)2 dimethyl zinc 11 E' 134 99 -35 1.353
HCNO fulminic acid 5 Π 224 535 311 0.419
C5H8 1,4-Pentadiene 16 A 137 288 151 0.476
C6H10 1,5-Hexadiene 14 Ag 351 255 -96 1.376
C6H10 1,5-Hexadiene 29 Bg 264 174 -90 1.519
COBr2 Carbonic dibromide 6 B2 512 363 -149 1.412
COBr2 Carbonic dibromide 4 B1 757 538 -219 1.407
CH3SSCH3 Disulfide, dimethyl 13 A 117 94 -23 1.243
CH2D2 methane-d2 6 B1 3013 2192 -821 1.374
CH2D2 methane-d2 8 B2 2234 2960 726 0.755
C2F2 difluoroacetylene 4 Πg 270 484 214 0.558
C4N2 2-Butynedinitrile 3 Σg 692 576 -116 1.202
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.676
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.676
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 360 -96 1.267
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 360 -96 1.266
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 360 -96 1.267
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 360 -96 1.266
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 129 -42 1.327
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 129 -42 1.322
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 129 -42 1.327
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 129 -42 1.322
C2H5 Ethyl radical 9 A' 528 428 -100 1.235
C2H Ethynyl radical 3 Π 372 550 178 0.676
C2H+ Ethynyl cation 3 Π 550 865 316 0.635
CH3 Methyl radical 2 A2" 606 291 -316 2.087
CH3 Methyl radical 2 A2" 606 291 -316 2.087
CH3 Methyl radical 2 A2" 606 291 -316 2.087
CH3 Methyl radical 2 A2" 606 291 -316 2.087
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 90 -268 3.962
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 132 -132 2.006
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 850 -286 1.336
CH2OH Hydroxymethyl radical 9 A 234 368 134 0.636
CH2OH Hydroxymethyl radical 8 A 482 750 268 0.643
C2Cl2+ dichloroacetylene cation 4 Πg 318 460 142 0.691
C2Cl2+ dichloroacetylene cation 5 Πu 233 193 -40 1.207
GaF3 Gallium trifluoride 4 E' 192 130 -62 1.475
FOOF Perfluoroperoxide 2 A 630 1053 423 0.598
FOOF Perfluoroperoxide 3 A 360 520 160 0.692
FOOF Perfluoroperoxide 5 B 614 1046 432 0.587
CaF2 Calcium difluoride 2 A1 120 65 -55 1.841
N2O3 Dinitrogen trioxide 6 A' 241 406 165 0.593
N2O3 Dinitrogen trioxide 7 A' 205 335 130 0.611
N2O3 Dinitrogen trioxide 8 A" 414 641 227 0.646
N2O3 Dinitrogen trioxide 9 A" 63 115 52 0.547
NS Mononitrogen monosulfide 1 Σ 1219 841 -378 1.449
SiN Silicon nitride 1 Σ 1151 875 -276 1.315
PCl5 Phosphorus pentachloride 2 A1' 370 275 -95 1.348
ZnCN Zinc monocyanide 3 Π 212 171 -41 1.237
PS phosphorus sulfide 1 Σ 739 491 -248 1.505
CP Carbon monophosphide 1 Σ 1240 923 -317 1.343
N2O4 Dinitrogen tetroxide 3 Ag 265 422 157 0.628
N2O4 Dinitrogen tetroxide 4 Au 82 67 -15 1.229
Li2O dilithium oxide 3 Πu 112 166 54 0.672
C3 carbon trimer 3 Πu 63 114 51 0.555
C3 carbon trimer 3 Πu 63 114 51 0.555
C3 carbon trimer 3 Πu 63 114 51 0.555
C3 carbon trimer 3 Πu 63 114 51 0.555
CaOH Calcium monohydroxide 2 Σ 353 587 234 0.602
CaOH Calcium monohydroxide 3 Π 609 342 -267 1.779
SF5Cl sulfur chloropentafluoride 11 E 397 268 -129 1.482
SiH- silicon monohydride anion 1 Σ 2175 1750 -425 1.243
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
SiH- silicon monohydride anion 1 Σ 2175 1750 -425 1.243
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
SF5Cl sulfur chloropentafluoride 5 B1 625 507 -118 1.232
SF5Cl sulfur chloropentafluoride 7 B2 505 343 -162 1.471
PN+ phosphorus nitride cation 1 Σ 1200 771 -429 1.557
H3O+ hydronium 2 A1 954 756 -198 1.262
F3- trifluoride anion 2 Σu 550 -365 -915 -1.509
ZnH2 Zinc hydride 3 Πu 633 453 -179 1.396
AlO Aluminum monoxide 1 Σ 979 737 -243 1.329
ClOO chloroperoxy radical 1 A' 1443 1097 -346 1.316
ClOO chloroperoxy radical 2 A' 414 672 259 0.615
ClOO chloroperoxy radical 3 A' 201 426 225 0.473
Cl3- trichloride anion 2 Σu 327 -97 -424 -3.370
ZnCH3 Zinc monomethyl 6 E 315 567 252 0.555
ONONO Nitrosyl nitrite 9 B2 380 714 334 0.532
GeH2 germylene 1 A1 1856 935 -921 1.986
H2POH Phosphinous acid 9 A" 375 268 -107 1.401
Mg2 Magnesium diatomic 1 Σg 51 339 288 0.151
Mg2 Magnesium diatomic 1 Σg 51 339 288 0.151
Mg2 Magnesium diatomic 1 Σg 51 339 288 0.151
Mg2 Magnesium diatomic 1 Σg 51 339 288 0.151
Al2 Aluminum diatomic 1 Σg 286 456 171 0.626
NNS Nitrogen sulfide 2 Σ 752 563 -189 1.335