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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**
Calculated values were scaled by 0.9026.

Species Name mode Symmetry Experiment Theory difference ratio
CH3CONH2 Acetamide 20 A 259 115 -144 2.260
C3H4O2 β–Propiolactone 21 A" 113 172 59 0.657
CH3OH Methyl alcohol 12 A" 200 308 108 0.649
CH3OH Methyl alcohol 12 A" 200 308 108 0.650
CH3OH Methyl alcohol 12 A" 200 308 108 0.649
CH3OH Methyl alcohol 12 A" 200 308 108 0.650
CH3COCH3 Acetone 12 A2 77 48 -29 1.608
C2H6O2S Dimethyl sulfone 20 B1 262 212 -50 1.236
CHONH2 formamide 12 A" 289 177 -111 1.629
CH3COCl Acetyl Chloride 15 A" 166 137 -29 1.209
CBr2F2 Methane, dibromodifluoro- 3 A1 140 332 192 0.422
C3F8 perfluoropropane 13 A2 276 220 -56 1.257
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 62 -13 1.206
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 525 -107 1.203
CH3COCH2CH3 2-Butanone 33 A" 87 28 -59 3.134
CH3COOCH3 methyl acetate 27 A" 110 86 -24 1.277
C6H4O2 parabenzoquinone 30 B3u 109 88 -20 1.228
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.205
C3H6O 2-Propen-1-ol 24 A 188 109 -79 1.722
C5H12 Pentane 23 A2 131 102 -29 1.283
C4H8O Furan, tetrahydro- 17 A 286 237 -49 1.209
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 161 -32 1.201
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.201
C5H8 Cyclopentene 18 A' 254 132 -122 1.917
NH2CN cyanamide 5 A' 408 589 181 0.693
C2H2N4 sym-tetrazine 18 B3u 254 369 115 0.688
C6H4 Benzyne 24 B2 472 283 -189 1.670
C4H6O2 2,3-Butanedione 21 Bg 240 119 -121 2.014
C2H3NO3 Oxamic acid 15 A' 328 269 -59 1.221
C2H3NO3 Oxamic acid 17 A" 815 640 -175 1.274
C2H3NO3 Oxamic acid 18 A" 745 586 -159 1.272
C2H3NO3 Oxamic acid 21 A" 162 51 -111 3.184
HCNO fulminic acid 5 Π 224 553 329 0.405
C3H6O Oxetane 12 A2 986 815 -171 1.210
C2H3NO3 Oxamic acid 3 A' 2600 3474 874 0.748
Zn(CH3)2 dimethyl zinc 11 E' 134 107 -27 1.249
C5H8 1,4-Pentadiene 16 A 137 289 152 0.475
C6H10 1,5-Hexadiene 14 Ag 351 256 -95 1.371
C6H10 1,5-Hexadiene 29 Bg 264 166 -98 1.595
COBr2 Carbonic dibromide 4 B1 757 521 -236 1.454
COBr2 Carbonic dibromide 6 B2 512 351 -161 1.460
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.269
CH2D2 methane-d2 6 B1 3013 2197 -816 1.372
CH2D2 methane-d2 8 B2 2234 2965 731 0.754
C2F2 difluoroacetylene 4 Πg 270 412 142 0.656
CaO Calcium monoxide 1 Σ 732 525 -207 1.395
NaOH sodium hydroxide 3 Π 300 211 -89 1.420
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 120 -51 1.421
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 122 -49 1.406
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 120 -51 1.421
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 122 -49 1.406
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 357 -99 1.276
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 357 -99 1.277
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 357 -99 1.276
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 357 -99 1.277
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.673
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C2H+ Ethynyl cation 3 Π 550 838 289 0.655
CH3 Methyl radical 2 A2" 606 307 -299 1.973
CH3 Methyl radical 2 A2" 606 307 -299 1.973
CH3 Methyl radical 2 A2" 606 307 -299 1.973
CH3 Methyl radical 2 A2" 606 307 -299 1.973
CH2OH Hydroxymethyl radical 8 A 482 747 265 0.645
CH2OH Hydroxymethyl radical 9 A 234 366 132 0.640
C2H5 Ethyl radical 9 A' 528 416 -113 1.271
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 126 -138 2.100
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 88 -270 4.056
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 856 -280 1.326
C3H3 Propargyl radical 7 B1 490 404 -86 1.214
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.267
CuCl Copper monochloride 1 Σ 418 344 -73 1.213
MgF2 Magnesium fluoride 3 Πu 165 136 -29 1.216
AsH3+ Arsine cation 2 A1 452 708 256 0.638
FOOF Perfluoroperoxide 5 B 614 1025 411 0.599
FOOF Perfluoroperoxide 2 A 630 1033 403 0.610
ZnCN Zinc monocyanide 3 Π 212 162 -50 1.308
NS Mononitrogen monosulfide 1 Σ 1219 807 -412 1.511
PCl5 Phosphorus pentachloride 2 A1' 370 272 -98 1.361
SiN Silicon nitride 1 Σ 1151 826 -326 1.394
MgOH magnesium hydroxide 3 Π 188 125 -63 1.503
CP Carbon monophosphide 1 Σ 1240 912 -328 1.359
S3- Sulfur trimer anion 3 B2 594 468 -126 1.270
N2O4 Dinitrogen tetroxide 3 Ag 265 416 151 0.637
N2O4 Dinitrogen tetroxide 4 Au 82 59 -23 1.395
N2O3 Dinitrogen trioxide 6 A' 241 405 164 0.595
N2O3 Dinitrogen trioxide 7 A' 205 337 132 0.609
N2O3 Dinitrogen trioxide 8 A" 414 620 206 0.668
N2O3 Dinitrogen trioxide 9 A" 63 104 41 0.607
CuH Copper monohydride 1 Σ 1941 1609 -332 1.207
CuH Copper monohydride 1 Σ 1941 1609 -332 1.207
CuH Copper monohydride 1 Σ 1941 1609 -332 1.207
CuH Copper monohydride 1 Σ 1941 1609 -332 1.207
C3 carbon trimer 3 Πu 63 138 74 0.460
CaOH Calcium monohydroxide 2 Σ 353 583 230 0.606
CaOH Calcium monohydroxide 3 Π 609 380 -229 1.601
SF5Cl sulfur chloropentafluoride 11 E 397 260 -137 1.526
PS phosphorus sulfide 1 Σ 739 494 -245 1.496
SiH- silicon monohydride anion 1 Σ 2175 1746 -429 1.245
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
SiH- silicon monohydride anion 1 Σ 2175 1746 -429 1.245
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
SF5Cl sulfur chloropentafluoride 5 B1 625 478 -147 1.308
SF5Cl sulfur chloropentafluoride 7 B2 505 332 -173 1.522
ClOO chloroperoxy radical 1 A' 1443 1075 -368 1.342
ClOO chloroperoxy radical 2 A' 414 645 231 0.642
ClOO chloroperoxy radical 3 A' 201 409 208 0.492
PN+ phosphorus nitride cation 1 Σ 1200 684 -516 1.755
HOClO Chlorous acid 3 A 978 781 -197 1.253
AlO Aluminum monoxide 1 Σ 979 731 -249 1.341
GeH2 germylene 2 A1 916 1934 1018 0.474
H2POH Phosphinous acid 9 A" 375 268 -108 1.402
Mg2 Magnesium diatomic 1 Σg 51 337 286 0.152
Mg2 Magnesium diatomic 1 Σg 51 337 286 0.152
Mg2 Magnesium diatomic 1 Σg 51 337 286 0.152
Mg2 Magnesium diatomic 1 Σg 51 337 286 0.152
BrO Bromine monoxide 1 Σ 726 576 -150 1.261
NBr nitrogen monobromide 1 Σ 692 536 -156 1.290
H3O+ hydronium 2 A1 954 705 -250 1.354
ZnH2 Zinc hydride 3 Πu 633 484 -148 1.306
GeH2 germylene 1 A1 1856 927 -929 2.002
F3- trifluoride anion 2 Σu 550 -268 -818 -2.052
ClS2 Sulfur chloride 1 A' 662 542 -120 1.222
ZnCH3 Zinc monomethyl 6 E 315 585 270 0.539
Cl3- trichloride anion 2 Σu 327 43 -284 7.578
NNS Nitrogen sulfide 2 Σ 752 529 -223 1.422
ONONO Nitrosyl nitrite 9 B2 380 713 333 0.533