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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
C6H6 Benzene 8 B2g 703 488 -215 1.440
CBr2F2 Methane, dibromodifluoro- 3 A1 140 330 190 0.424
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 53 -22 1.427
CH3COOCH3 methyl acetate 27 A" 110 52 -58 2.116
C6H5CHO benzaldehyde 32 A" 688 495 -193 1.391
C3H6O 2-Propen-1-ol 21 A 554 428 -126 1.295
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
C5H8 Cyclopentene 18 A' 254 166 -88 1.530
C2H3N3 1H-1,2,4-Triazole 18 A" 640 499 -141 1.284
C4H2 Diacetylene 7 Πg 482 192 -290 2.510
HCNO fulminic acid 5 Π 224 171 -53 1.311
C6H10 1,5-Hexadiene 14 Ag 351 260 -91 1.350
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.217
C6H8 1,3,5-Hexatriene, (E)- 24 Bg 217 177 -40 1.223
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)- 32 A" 171 109 -62 1.562
C2Cl2 dichloroacetylene 4 Πg 333 152 -181 2.190
BF3+ boron trifluoride cation 3 E' 1662 595 -1066 2.791
CaF2 Calcium difluoride 2 A1 120 55 -65 2.183
N2O3 Dinitrogen trioxide 9 A" 63 137 74 0.460
Li2O dilithium oxide 3 Πu 112 55 -56 2.025
CaOH Calcium monohydroxide 3 Π 609 355 -254 1.716
S3- Sulfur trimer anion 3 B2 594 475 -119 1.251
SiH- silicon monohydride anion 1 Σ 2175 1768 -407 1.230
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.254
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 325 111 0.658
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 524 -108 1.206
C4H8O Furan, tetrahydro- 33 B 137 16 -121 8.530
C4H8O2 1,4-Dioxane 19 Au 288 236 -52 1.219
C3H3NO Isoxazole 14 A" 1033 858 -175 1.204
C4H4N2 Pyridazine 13 A2 421 340 -81 1.237
NH2CN cyanamide 5 A' 408 685 277 0.595
GeH2 germylene 1 A1 1856 929 -927 1.999
ZnCH3 Zinc monomethyl 6 E 315 592 277 0.532
C6H10 1,5-Hexadiene 20 Au 649 541 -108 1.201
COBr2 Carbonic dibromide 6 B2 512 342 -170 1.499
ZnS Zinc sulfide 1 Σ 459 344 -115 1.335
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.388
C5H8 1,3-Pentadiene, (E)- 31 A" 361 234 -127 1.540
C4H6 Methylenecyclopropane 17 B1 360 268 -92 1.344
CaOH Calcium monohydroxide 2 Σ 353 621 268 0.568
C4 Carbon tetramer 4 Πg 323 248 -75 1.303
C6H10 1,5-Hexadiene 29 Bg 264 154 -110 1.717
COBr2 Carbonic dibromide 4 B1 757 499 -258 1.517
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.222
C5H8 1,3-Pentadiene, (E)- 32 A" 129 189 60 0.684
C2H+ Ethynyl cation 3 Π 550 785 236 0.700
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.325
BF3+ boron trifluoride cation 4 E' 411 -1024 -1435 -0.401
ZnCl Zinc monochloride 1 Σ 391 298 -93 1.312
PCl5 Phosphorus pentachloride 2 A1' 370 268 -102 1.383
C3H4O2 β–Propiolactone 21 A" 113 165 52 0.683
CH3OH Methyl alcohol 12 A" 200 325 125 0.615
CH3NH2 methyl amine 14 A" 1195 945 -250 1.265
C3H6O 2-Propen-1-ol 24 A 188 109 -79 1.721
C5H12 Pentane 23 A2 131 91 -40 1.444
CH3CCCH3 2-Butyne 16 E" 371 293 -78 1.266