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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 MP2FC/CEP-121G*
Calculated values were scaled by 0.9528.

Species Name mode Symmetry Experiment Theory difference ratio
CH2CHO Vinyloxy radical 12 A" 404 321 -83 1.259
C4H6 Methylenecyclopropane 17 B1 360 253 -107 1.423
ClFO3 Perchloryl fluoride 3 A1 549 441 -108 1.244
ClFO3 Perchloryl fluoride 6 E 405 314 -91 1.288
O2+ diatomic oxygen cation 1 Σg 1906 1217 -689 1.566
C3 carbon trimer 3 Πu 63 308 244 0.206
C5H5- cylopentadienyl anion 4 A2" 710 590 -120 1.204
C4 Carbon tetramer 4 Πg 323 523 200 0.617
ClONO2 Chlorine nitrate 6 A' 434 361 -73 1.201
ClOO chloroperoxy radical 2 A' 414 1024 610 0.404
NCO isocyanato radical 1 Σ 1921 2353 432 0.816
Mg2 Magnesium diatomic 1 Σg 51 31 -20 1.666
CH2CO Ketene 6 B1 528 396 -132 1.332
C6H6 Fulvene 14 A2 666 555 -111 1.201
C6H10 1,5-Hexadiene 20 Au 649 532 -117 1.221
C6H10 2-Hexyne 38 A" 392 235 -157 1.670
C6H10 2-Hexyne 40 A" 220 161 -59 1.363
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 305 -151 1.497
C5H8 1,3-Pentadiene, (E)- 31 A" 361 228 -133 1.587
CN Cyano radical 1 Σ 2069 2661 592 0.777
C6H5O phenoxy radical 19 B1 472 175 -297 2.692
C2H Ethynyl radical 2 Σ 1841 2307 466 0.798
C6H5 phenyl 18 B1 415 150 -265 2.768
C4H5N Pyrrole 11 A2 692 574 -118 1.206
C4H8O Furan, tetrahydro- 33 B 137 31 -106 4.443
C4H4O Furan 9 A2 838 675 -163 1.242
C4H4S Thiophene 9 A2 867 714 -153 1.214
C4H4S Thiophene 11 A2 567 418 -149 1.358
C2Cl4 Tetrachloroethylene 4 Au 110 89 -21 1.231
C5H8 Cyclopentene 29 A" 1082 897 -185 1.207
C3H3NO Isoxazole 14 A" 1033 771 -262 1.340
C2H3N3 1H-1,2,4-Triazole 14 A" 990 790 -200 1.253
C4H4N2 Pyridazine 13 A2 421 217 -204 1.937
NH2CN cyanamide 5 A' 408 731 323 0.558
CH3COOH Acetic acid 11 A' 657 547 -110 1.201
C2H6O2S Dimethyl sulfone 20 B1 262 212 -50 1.238
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 323 109 0.663
HCN+ hydrogen cyanide cation 2 Σ 1800 2794 994 0.644
CH3CCH propyne 9 E 633 499 -134 1.268
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.219
C2Cl2+ dichloroacetylene cation 4 Πg 318 264 -53 1.202
NO2 Nitrogen dioxide 3 B2 1618 2040 422 0.793
N2O4 Dinitrogen tetroxide 9 B2u 265 177 -88 1.501
NS+ nitrogen sulfide cation 1 Σ 1415 1145 -270 1.236
Li2O dilithium oxide 3 Πu 112 83 -29 1.345
PS phosphorus sulfide 1 Σ 739 1143 404 0.647
ClOO chloroperoxy radical 3 A' 201 466 265 0.432
C3O2 Carbon suboxide 7 Πu 61 169 108 0.360
C6H4F2 1,4-difluorobenzene 7 Au 945 767 -178 1.232
C6H4F2 1,4-difluorobenzene 16 B2g 692 385 -307 1.796
C5H8 1,4-Pentadiene 16 A 137 289 152 0.474
C6H10 1,5-Hexadiene 14 Ag 351 261 -90 1.346
CO+ carbon monoxide cation 1 Σ 2214 2714 500 0.816
C3H6O2 1,3-Dioxolane 6 A 1361 2879 1518 0.473
C3H6O2 1,3-Dioxolane 13 A 658 1217 559 0.541
C6H10 2-Hexyne 24 A' 272 214 -58 1.273
C4H2N2 Fumaronitrile 18 Bu 148 121 -27 1.219
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 173 -44 1.251
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 102 -69 1.671
C2H5 Ethyl radical 9 A' 528 437 -91 1.207
C2H Ethynyl radical 3 Π 372 785 413 0.474
C6H5 phenyl 17 B1 655 452 -203 1.448
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 854 -282 1.330
C6H8 1,3,5-Hexatriene, (Z)- 17 A2 709 569 -140 1.245
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 103 -161 2.570
CH3COOH Acetic acid 18 A" 93 52 -41 1.790
C2H2 Acetylene 4 Πg 612 335 -277 1.826
CH3COOCH3 methyl acetate 27 A" 110 17 -93 6.561
C6H4O2 parabenzoquinone 16 B2g 794 496 -298 1.602
C6H4O2 parabenzoquinone 30 B3u 109 75 -34 1.454
C3H6O 2-Propen-1-ol 21 A 554 421 -133 1.317
C3H2N2 Malononitrile 6 A1 167 130 -37 1.283
C4H4O Furan 11 A2 603 385 -218 1.566
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 140 -53 1.379
C5H8 Cyclopentene 18 A' 254 175 -79 1.451
C2Cl2+ dichloroacetylene cation 5 Πu 233 179 -54 1.301
FNO3 Fluorine nitrate 6 A' 455 378 -77 1.205
PCl5 Phosphorus pentachloride 2 A1' 370 285 -85 1.300
FO Oxygen monofluoride 1 Σ 1053 1534 481 0.686
C5H5- cylopentadienyl anion 8 E1" 625 416 -209 1.503
C5H5- cylopentadienyl anion 14 E2" 600 104 -496 5.751
AlO Aluminum monoxide 1 Σ 979 589 -390 1.662
SCN thiocyanato radical 1 Σ 1942 2459 517 0.790
B2H6 Diborane 11 B2g 850 701 -149 1.212
C5H12 Pentane 23 A2 131 92 -39 1.430
C4H5N Pyrrole 10 A2 864 674 -190 1.281
C4H4N2 Succinonitrile 17 Bg 387 309 -78 1.252
C2H3N3 1H-1,2,4-Triazole 15 A" 885 726 -159 1.219
C4H4N2 Pyridazine 12 A2 751 433 -318 1.735
C4H6O2 2,3-Butanedione 9 Ag 614 498 -116 1.233
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.218
C4H2 Diacetylene 6 Πg 627 1132 505 0.554
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 137 -33 1.238
C4H6 Cyclobutene 13 A2 325 267 -58 1.218
C2H+ Ethynyl cation 3 Π 550 802 253 0.685
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 88 -270 4.068
CCl3 Trichloromethyl radical 2 A1 251 366 115 0.685
C6H6 Fulvene 15 A2 494 370 -124 1.335
C6H6 Fulvene 17 B1 907 744 -163 1.220
C5H8 1,4-Pentadiene 17 A 102 81 -21 1.255
C6H10 1,5-Hexadiene 29 Bg 264 137 -127 1.926
C3H6O2 1,3-Dioxolane 4 A 1509 2945 1436 0.512
C2F2 difluoroacetylene 4 Πg 270 104 -166 2.603
C6H10 2-Hexyne 25 A' 115 88 -27 1.304
CH3OH Methyl alcohol 12 A" 200 336 136 0.595
CH3NH2 methyl amine 14 A" 1195 937 -258 1.275
HCN+ hydrogen cyanide cation 1 Σ 3050 3809 759 0.801
CH2CCl2 Ethene, 1,1-dichloro- 7 B1 875 720 -155 1.215
N(CH3)3 Trimethylamine 11 A2 255 206 -49 1.235
C6H4O2 parabenzoquinone 17 B2g 241 -302 -543 -0.799
C3H6O 2-Propen-1-ol 24 A 188 105 -83 1.789
ClFO3 Perchloryl fluoride 2 A1 715 596 -119 1.200
BF3+ boron trifluoride cation 3 E' 1662 2119 458 0.784
O3 Ozone 3 B2 1042 2339 1297 0.445
NO+ nitric oxide cation 1 Σ 2377 1924 -453 1.236
N2O3 Dinitrogen trioxide 7 A' 205 170 -35 1.208
N2O3 Dinitrogen trioxide 9 A" 63 150 87 0.421
MgOH magnesium hydroxide 3 Π 188 65 -123 2.907
SiH- silicon monohydride anion 1 Σ 2175 1747 -428 1.245
PO Phosphorus monoxide 1 Σ 1233 5220 3987 0.236
PO+ phosphorus monoxide cation 1 Σ 1405 1165 -240 1.206
PN Phosphorus mononitride 1 Σ 1337 1069 -268 1.251
C4N2 2-Butynedinitrile 3 Σg 692 563 -129 1.229
LiOH lithium hydroxide 3 Π 257 385 129 0.665
CH3 Methyl radical 2 A2" 606 404 -202 1.500
C6H8 1,3,5-Hexatriene, (Z)- 18 A2 331 248 -83 1.334
HCCF Fluoroacetylene 5 Π 367 302 -65 1.215
C6H4F2 1,4-difluorobenzene 15 B2g 928 750 -178 1.238
C6H4F2 1,4-difluorobenzene 18 B2g 374 -292 -666 -1.282
C5H8 1,4-Pentadiene 31 B 721 560 -161 1.287
C5H8 1,4-Pentadiene 33 B 331 83 -248 3.965
C3H8O2S (Methylsulphonyl)ethane 32 ?a 324 267 -57 1.216
C5H6S Thiophene, 3-methyl- 27 A" 594 429 -165 1.386
CH3SSCH3 Disulfide, dimethyl 13 A 117 86 -31 1.363
C3H6O2 1,3-Dioxolane 5 A 1480 2914 1434 0.508
C4H5N Pyrrole 12 A2 614 407 -207 1.507
C2Cl4 Tetrachloroethylene 7 B2g 512 344 -168 1.490
C2H3N3 1H-1,2,4-Triazole 18 A" 640 509 -131 1.257
C4H4N2 Pyrazine 6 Au 960 798 -162 1.204
CH3CONH2 Acetamide 20 A 259 390 131 0.663
C2H4 Ethylene 7 B2g 940 773 -167 1.215