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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 MP2=FULL/6-31+G**
Calculated values were scaled by 0.9392.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 11 A' 657 545 -112 1.205
CH3COOH Acetic acid 18 A" 93 64 -29 1.458
CH3OH Methyl alcohol 12 A" 200 304 104 0.658
CH3OH Methyl alcohol 12 A" 200 306 106 0.654
CH3OH Methyl alcohol 12 A" 200 304 104 0.658
CH3OH Methyl alcohol 12 A" 200 306 106 0.654
C2H2 Acetylene 4 Πg 612 451 -161 1.358
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 314 100 0.682
HCN+ hydrogen cyanide cation 1 Σ 3050 3723 674 0.819
HCN+ hydrogen cyanide cation 2 Σ 1800 2777 977 0.648
CH3CCH propyne 10 E 328 252 -76 1.303
CH3COCl Acetyl Chloride 15 A" 166 122 -44 1.361
CBr2F2 Methane, dibromodifluoro- 3 A1 140 326 186 0.430
C3F8 perfluoropropane 13 A2 276 214 -62 1.292
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 517 -115 1.221
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 59 -16 1.271
CH3COOCH3 methyl acetate 27 A" 110 35 -75 3.118
C9H8 Indene 40 A" 690 428 -262 1.613
C9H8 Indene 41 A" 549 351 -198 1.565
C9H8 Indene 42 A" 415 335 -80 1.238
C9H8 Indene 43 A" 388 181 -207 2.143
C9H8 Indene 44 A" 206 159 -47 1.295
C9H8 Indene 45 A" 189 -444 -633 -0.425
C6H5CN phenyl cyanide 19 B1 688 439 -249 1.567
C6H5CN phenyl cyanide 20 B1 542 346 -196 1.567
C6H5CN phenyl cyanide 21 B1 372 239 -133 1.557
C6H5CN phenyl cyanide 22 B1 141 116 -25 1.214
C6H5CHO benzaldehyde 32 A" 688 385 -303 1.789
C6H5CHO benzaldehyde 33 A" 450 355 -95 1.268
C6H5CHO benzaldehyde 34 A" 400 304 -96 1.314
C6H5CHO benzaldehyde 36 A" 111 89 -22 1.247
C6H4O2 parabenzoquinone 16 B2g 794 532 -262 1.492
C6H4O2 parabenzoquinone 17 B2g 241 -33 -274 -7.303
C6H4O2 parabenzoquinone 30 B3u 109 76 -33 1.432
CH2CHCHCH2 1,3-Butadiene 13 Au 162 131 -31 1.237
C3H3N acrylonitrile 15 A" 362 301 -61 1.201
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.773
C6H5Cl chlorobenzene 18 B1 685 405 -280 1.691
C6H5Cl chlorobenzene 19 B1 467 296 -171 1.579
C5H12 Pentane 23 A2 131 99 -32 1.324
C3H2N2 Malononitrile 6 A1 167 133 -34 1.256
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 154 -39 1.255
C5H8 Cyclopentene 18 A' 254 177 -77 1.432
C5H8 Cyclopentene 29 A" 1082 900 -182 1.202
C2H3N3 1H-1,2,4-Triazole 14 A" 990 817 -173 1.212
C2H3N3 1H-1,2,4-Triazole 18 A" 640 518 -122 1.235
NH2CN cyanamide 5 A' 408 620 212 0.658
C6H5F Fluorobenzene 18 B1 685 465 -220 1.474
C6H5F Fluorobenzene 19 B1 500 359 -141 1.391
C4H6O2 2,3-Butanedione 9 Ag 614 499 -115 1.230
C4H6O2 2,3-Butanedione 13 Au 1111 923 -188 1.203
C4H6O2 2,3-Butanedione 21 Bg 240 107 -133 2.250
CH3CCCH3 2-Butyne 16 E" 371 203 -168 1.829
C3O2 Carbon suboxide 7 Πu 61 155 94 0.394
C6H4F2 1,4-difluorobenzene 16 B2g 692 418 -274 1.655
C6H4F2 1,4-difluorobenzene 18 B2g 374 309 -65 1.212
C5H8 1,4-Pentadiene 16 A 137 287 150 0.478
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.205
COBr2 Carbonic dibromide 4 B1 757 507 -250 1.494
COBr2 Carbonic dibromide 6 B2 512 335 -177 1.528
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.256
CH2D2 methane-d2 6 B1 3013 2274 -739 1.325
CH2D2 methane-d2 8 B2 2234 3070 836 0.728
LiOH lithium hydroxide 3 Π 257 489 232 0.525
CO+ carbon monoxide cation 1 Σ 2214 2717 503 0.815
CO+ carbon monoxide cation 1 Σ 2214 2717 503 0.815
CO+ carbon monoxide cation 1 Σ 2214 2717 503 0.815
CO+ carbon monoxide cation 1 Σ 2214 2717 503 0.815
C4H6 Cyclobutene 13 A2 325 269 -56 1.208
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.680
GeO2 Germanium dioxide 3 Πu 196 162 -33 1.206
NaOH sodium hydroxide 3 Π 300 456 156 0.658
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 313 -143 1.457
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 313 -143 1.458
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 313 -143 1.457
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 313 -143 1.458
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 95 -76 1.792
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 96 -75 1.786
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 95 -76 1.792
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 96 -75 1.786
CN Cyano radical 1 Σ 2069 2689 620 0.769
C6H5O phenoxy radical 19 B1 472 374 -98 1.262
C2H Ethynyl radical 2 Σ 1841 2327 486 0.791
C2H Ethynyl radical 3 Π 372 757 386 0.491
CH3OO methylperoxy radical 12 A" 170 120 -50 1.418
CH3 Methyl radical 2 A2" 606 446 -160 1.359
CH3 Methyl radical 2 A2" 606 446 -160 1.359
CH3 Methyl radical 2 A2" 606 446 -160 1.359
CH3 Methyl radical 2 A2" 606 446 -160 1.359
CH2OH Hydroxymethyl radical 8 A 482 695 213 0.693
CH2OH Hydroxymethyl radical 9 A 234 428 194 0.547
C2Cl2+ dichloroacetylene cation 5 Πu 233 170 -63 1.370
BF3+ boron trifluoride cation 3 E' 1662 2092 431 0.794
C4H6 Methylenecyclopropane 17 B1 360 245 -115 1.467
CH2CHO Vinyloxy radical 10 A" 703 1008 305 0.697
CH2CHO Vinyloxy radical 12 A" 404 326 -78 1.240
ClFO3 Perchloryl fluoride 3 A1 549 456 -93 1.204
ClFO3 Perchloryl fluoride 6 E 405 328 -77 1.236
SiO2 silicon dioxide 3 Πu 273 203 -69 1.341
O2+ diatomic oxygen cation 1 Σg 1906 1277 -629 1.492
O2+ diatomic oxygen cation 1 Σg 1906 1277 -629 1.492
O2+ diatomic oxygen cation 1 Σg 1906 1277 -629 1.492
O2+ diatomic oxygen cation 1 Σg 1906 1277 -629 1.492
FOOF Perfluoroperoxide 3 A 360 244 -116 1.477
FOOF Perfluoroperoxide 4 A 202 127 -75 1.595
AsH3+ Arsine cation 2 A1 452 676 224 0.668
FNO3 Fluorine nitrate 6 A' 455 355 -100 1.282
NO Nitric oxide 1 Σ 1904 3600 1696 0.529
NS+ nitrogen sulfide cation 1 Σ 1415 1166 -249 1.213
NO2 Nitrogen dioxide 3 B2 1618 2193 575 0.738
O3 Ozone 3 B2 1042 2246 1204 0.464
FO Oxygen monofluoride 1 Σ 1053 2170 1117 0.485
FO Oxygen monofluoride 1 Σ 1053 2170 1117 0.485
FO Oxygen monofluoride 1 Σ 1053 2170 1117 0.485
FO Oxygen monofluoride 1 Σ 1053 2170 1117 0.485
C3 carbon trimer 3 Πu 63 129 66 0.491
C3 carbon trimer 3 Πu 63 129 65 0.493
C3 carbon trimer 3 Πu 63 129 66 0.491
C3 carbon trimer 3 Πu 63 129 65 0.493
C5H5- cylopentadienyl anion 4 A2" 710 591 -119 1.201
C5H5- cylopentadienyl anion 14 E2" 600 472 -128 1.272
CaOH Calcium monohydroxide 2 Σ 353 544 191 0.649
CaOH Calcium monohydroxide 3 Π 609 410 -199 1.484
N2O3 Dinitrogen trioxide 7 A' 205 167 -38 1.231
N2O3 Dinitrogen trioxide 9 A" 63 152 89 0.415
PS phosphorus sulfide 1 Σ 739 1204 465 0.614
SCN thiocyanato radical 1 Σ 1942 2402 460 0.809
SF5Cl sulfur chloropentafluoride 5 B1 625 442 -183 1.415
SF5Cl sulfur chloropentafluoride 7 B2 505 301 -204 1.676
SF5Cl sulfur chloropentafluoride 11 E 397 241 -156 1.650
PO Phosphorus monoxide 1 Σ 1233 3112 1879 0.396
PO Phosphorus monoxide 1 Σ 1233 3108 1875 0.397
PO Phosphorus monoxide 1 Σ 1233 3112 1879 0.396
PO Phosphorus monoxide 1 Σ 1233 3108 1875 0.397
ClONO2 Chlorine nitrate 6 A' 434 340 -94 1.278
FO2 Dioxygen monofluoride 1 A' 1487 2777 1290 0.535
FO2 Dioxygen monofluoride 2 A' 579 1184 604 0.489
GeH2 germylene 1 A1 1856 931 -925 1.993
GeH2 germylene 2 A1 916 1981 1065 0.462
FO2 Dioxygen monofluoride 3 A' 376 627 251 0.600
H2POH Phosphinous acid 9 A" 375 262 -113 1.430
ClOO chloroperoxy radical 2 A' 414 1017 603 0.407
ClOO chloroperoxy radical 3 A' 201 464 262 0.434
PN Phosphorus mononitride 1 Σ 1337 1093 -244 1.223
Mg2 Magnesium diatomic 1 Σg 51 325 274 0.157
Mg2 Magnesium diatomic 1 Σg 51 325 274 0.157
Mg2 Magnesium diatomic 1 Σg 51 325 274 0.157
Mg2 Magnesium diatomic 1 Σg 51 325 274 0.157
AlO Aluminum monoxide 1 Σ 979 429 -550 2.283
NCO isocyanato radical 1 Σ 1921 2351 430 0.817
H2OH2O water dimer 8 A' 103 162 59 0.637
H2OH2O water dimer 11 A" 108 170 62 0.634
H2OH2O water dimer 12 A" 88 137 49 0.644
AsN Arsenic mononitride 1 Σ 1069 860 -208 1.242
Cl3- trichloride anion 2 Σu 327 267 -60 1.222
ZnCH3 Zinc monomethyl 6 E 315 612 297 0.515
NNS Nitrogen sulfide 1 Σ 2048 1685 -363 1.215
ONONO Nitrosyl nitrite 9 B2 380 -27 -407 -14.247
BrONO Bromine nitrite 4 A' 391 294 -97 1.329