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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 QCISD/6-311G**
Calculated values were scaled by 0.9541.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 165 52 0.683
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3OH Methyl alcohol 12 A" 200 327 127 0.612
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3OH Methyl alcohol 12 A" 200 327 127 0.612
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.254
C6H6 Benzene 8 B2g 703 488 -215 1.440
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 325 111 0.658
CBr2F2 Methane, dibromodifluoro- 3 A1 140 330 190 0.424
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 53 -22 1.427
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 524 -108 1.206
C6H5CHO benzaldehyde 32 A" 688 495 -193 1.391
CH3COOCH3 methyl acetate 27 A" 110 52 -58 2.116
C9H8 Indene 40 A" 690 533 -157 1.295
C5H12 Pentane 23 A2 131 91 -40 1.444
C3H6O 2-Propen-1-ol 24 A 188 109 -79 1.721
C6H5Cl chlorobenzene 18 B1 685 473 -212 1.448
C4H5N Pyrrole 16 B1 475 386 -88 1.228
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 143 -50 1.347
C4H8O2 1,4-Dioxane 19 Au 288 236 -52 1.219
C5H8 Cyclopentene 18 A' 254 166 -88 1.530
C2H3N3 1H-1,2,4-Triazole 18 A" 640 499 -141 1.284
NH2CN cyanamide 5 A' 408 685 277 0.595
C4H4N2 Pyridazine 13 A2 421 340 -81 1.237
HCNO fulminic acid 5 Π 224 171 -53 1.311
C4H2 Diacetylene 7 Πg 482 192 -290 2.510
CH3CCCH3 2-Butyne 16 E" 371 293 -78 1.266
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.350
C6H10 1,5-Hexadiene 20 Au 649 541 -108 1.201
C6H10 1,5-Hexadiene 29 Bg 264 154 -110 1.717
COBr2 Carbonic dibromide 4 B1 757 499 -258 1.517
COBr2 Carbonic dibromide 6 B2 512 342 -170 1.499
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.217
CH2D2 methane-d2 6 B1 3013 2237 -776 1.347
CH2D2 methane-d2 8 B2 2234 3021 787 0.740
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.222
ZnS Zinc sulfide 1 Σ 459 344 -115 1.335
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 177 -40 1.223
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C4N2 2-Butynedinitrile 3 Σg 692 571 -121 1.212
NaOH sodium hydroxide 3 Π 300 216 -84 1.390
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 328 -128 1.390
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 328 -128 1.390
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 109 -62 1.562
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.558
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 109 -62 1.562
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 110 -61 1.558
C2H+ Ethynyl cation 3 Π 550 785 236 0.700
CH3 Methyl radical 2 A2" 606 413 -194 1.469
C4H6 Methylenecyclopropane 17 B1 360 268 -92 1.344
C2Cl2 dichloroacetylene 4 Πg 333 152 -181 2.190
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.325
BF3+ boron trifluoride cation 4 E' 411 -1024 -1435 -0.401
BF3+ boron trifluoride cation 3 E' 1662 595 -1066 2.791
MgF2 Magnesium fluoride 3 Πu 165 136 -29 1.210
FOOF Perfluoroperoxide 1 A 1210 989 -221 1.224
CaF2 Calcium difluoride 2 A1 120 55 -65 2.183
ZnCl Zinc monochloride 1 Σ 391 298 -93 1.312
N2O3 Dinitrogen trioxide 9 A" 63 137 74 0.460
Li2O dilithium oxide 3 Πu 112 55 -56 2.025
C3 carbon trimer 3 Πu 63 38 -25 1.650
CaOH Calcium monohydroxide 2 Σ 353 621 268 0.568
CaOH Calcium monohydroxide 3 Π 609 355 -254 1.716
C4 Carbon tetramer 4 Πg 323 248 -75 1.303
S3- Sulfur trimer anion 3 B2 594 475 -119 1.251
SiH- silicon monohydride anion 1 Σ 2175 1768 -407 1.230
SiH- silicon monohydride anion 1 Σ 2175 1768 -407 1.230
SiH- silicon monohydride anion 1 Σ 2175 1768 -407 1.230
SiH- silicon monohydride anion 1 Σ 2175 1768 -407 1.230
SF5Cl sulfur chloropentafluoride 5 B1 625 464 -161 1.347
SF5Cl sulfur chloropentafluoride 7 B2 505 316 -189 1.599
PCl5 Phosphorus pentachloride 2 A1' 370 268 -102 1.383
SF5Cl sulfur chloropentafluoride 11 E 397 247 -150 1.608
Cl3- trichloride anion 2 Σu 327 186 -141 1.761
GeH2 germylene 1 A1 1856 929 -927 1.999
H2POH Phosphinous acid 9 A" 375 257 -118 1.461
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.559
ZnCH3 Zinc monomethyl 6 E 315 592 277 0.532