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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/6-31G(2df,p)
Calculated values were scaled by 0.9445.

Species Name mode Symmetry Experiment Theory difference ratio
ClOO chloroperoxy radical 2 A' 414 1069 656 0.387
NCO isocyanato radical 1 Σ 1921 2349 428 0.818
GeH2 germylene 1 A1 1856 936 -920 1.983
Mg2 Magnesium diatomic 1 Σg 51 322 271 0.159
Al2 Aluminum diatomic 1 Σg 286 456 171 0.626
ZnCH3 Zinc monomethyl 6 E 315 581 266 0.542
CH2CHO Vinyloxy radical 10 A" 703 1028 325 0.684
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.290
O2+ diatomic oxygen cation 1 Σg 1906 1416 -490 1.346
C3 carbon trimer 3 Πu 63 211 148 0.301
CaOH Calcium monohydroxide 2 Σ 353 617 264 0.572
Cu2 Copper dimer 1 Σg 265 401 137 0.659
CH3OCH2CN Methoxyacetonitrile 15 A' 243 169 -74 1.434
C5H8 1,3-Pentadiene, (E)- 31 A" 361 246 -115 1.466
CN Cyano radical 1 Σ 2069 2729 660 0.758
C2H Ethynyl radical 2 Σ 1841 2386 545 0.771
C2H3NO3 Oxamic acid 16 A" 984 797 -187 1.234
C2H3NO3 Oxamic acid 18 A" 745 616 -129 1.210
COBr2 Carbonic dibromide 6 B2 512 342 -170 1.499
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 186 -41 1.221
C6H10 2-Hexyne 38 A" 392 314 -78 1.248
C4H8O Furan, tetrahydro- 33 B 137 40 -97 3.443
C3H3NO Isoxazole 14 A" 1033 848 -185 1.218
C4H4N2 Pyridazine 13 A2 421 350 -71 1.204
CH2NN diazomethane 6 B1 406 110 -296 3.683
NH2CN cyanamide 5 A' 408 643 235 0.634
CH3COCH3 Acetone 12 A2 77 62 -15 1.247
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.255
HCN+ hydrogen cyanide cation 2 Σ 1800 2729 929 0.660
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.219
NO2 Nitrogen dioxide 3 B2 1618 3456 1838 0.468
N2O4 Dinitrogen tetroxide 9 B2u 265 191 -74 1.387
CaOH Calcium monohydroxide 3 Π 609 371 -238 1.641
ClOO chloroperoxy radical 3 A' 201 479 278 0.420
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C6H10 1,5-Hexadiene 14 Ag 351 258 -93 1.358
CO+ carbon monoxide cation 1 Σ 2214 2703 489 0.819
C3H6O2 1,3-Dioxolane 6 A 1361 2897 1536 0.470
C3H6O2 1,3-Dioxolane 13 A 658 1205 547 0.546
NaOH sodium hydroxide 3 Π 300 213 -87 1.408
C2H5 Ethyl radical 9 A' 528 427 -101 1.236
C2H Ethynyl radical 3 Π 372 821 449 0.453
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 853 -283 1.332
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 140 -124 1.886
C3H6O 2-Propen-1-ol 21 A 554 423 -131 1.311
C3H2N2 Malononitrile 6 A1 167 136 -31 1.231
C5H8 Cyclopentene 18 A' 254 175 -79 1.454
C2H4O3 trioxolane124 21 B 193 159 -34 1.214
C4H2 Diacetylene 7 Πg 482 390 -92 1.235
C4H2 Diacetylene 8 Πu 630 513 -117 1.227
C2H3NO3 Oxamic acid 21 A" 162 66 -96 2.438
C2H2 Acetylene 4 Πg 612 476 -136 1.285
CH3COOCH3 methyl acetate 27 A" 110 62 -48 1.781
C6H4O2 parabenzoquinone 30 B3u 109 86 -23 1.262
C2Cl2+ dichloroacetylene cation 5 Πu 233 181 -52 1.286
ZnCN Zinc monocyanide 3 Π 212 115 -97 1.841
PCl5 Phosphorus pentachloride 2 A1' 370 286 -84 1.293
NO Nitric oxide 1 Σ 1904 3260 1356 0.584
ZnH2 Zinc hydride 3 Πu 633 386 -246 1.639
AlO Aluminum monoxide 1 Σ 979 708 -272 1.384
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.278
C2H3NO3 Oxamic acid 17 A" 815 656 -159 1.242
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.232
C6H10 1,5-Hexadiene 29 Bg 264 179 -85 1.475
COBr2 Carbonic dibromide 4 B1 757 513 -244 1.476
C3H6O2 1,3-Dioxolane 4 A 1509 2917 1408 0.517
C2F2 difluoroacetylene 4 Πg 270 204 -66 1.323
C6H10 2-Hexyne 25 A' 115 91 -24 1.264
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.251
C5H8 1,3-Pentadiene, (E)- 32 A" 129 201 72 0.641
C2H+ Ethynyl cation 3 Π 550 804 254 0.684
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 96 -262 3.729
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.692
CH3OH Methyl alcohol 12 A" 200 317 117 0.631
CH3NH2 methyl amine 14 A" 1195 936 -259 1.277
HCN+ hydrogen cyanide cation 1 Σ 3050 3591 541 0.849
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.741
C5H12 Pentane 23 A2 131 104 -27 1.256
C4H6O2 2,3-Butanedione 9 Ag 614 501 -113 1.225
C4H6O2 2,3-Butanedione 21 Bg 240 118 -122 2.027
CaF2 Calcium difluoride 2 A1 120 87 -33 1.377
O3 Ozone 3 B2 1042 2090 1048 0.499
N2O3 Dinitrogen trioxide 9 A" 63 169 106 0.374
SO+ sulfur monoxide cation 1 Σ 1360 1129 -231 1.205
PN Phosphorus mononitride 1 Σ 1337 1113 -224 1.202
C5H8 1,4-Pentadiene 15 A 421 349 -72 1.205
C5H8 1,4-Pentadiene 31 B 721 587 -134 1.227
C5H8 1,4-Pentadiene 33 B 331 97 -234 3.418
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.233
C3H6O2 1,3-Dioxolane 5 A 1480 2911 1431 0.508
C4N2 2-Butynedinitrile 3 Σg 692 572 -120 1.209
CH3OCH2CN Methoxyacetonitrile 24 A" 113 85 -28 1.323
CH3 Methyl radical 2 A2" 606 384 -222 1.579
CBr2F2 Methane, dibromodifluoro- 3 A1 140 339 199 0.414
CH3COCH2CH3 2-Butanone 33 A" 87 38 -49 2.265
C3H6O 2-Propen-1-ol 22 A 377 312 -65 1.208
C4H6O2 2,3-Butanedione 13 Au 1111 914 -197 1.216