return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
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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" 200 327 127 0.612
C6H6 Benzene 8 B2g 703 488 -215 1.440
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 325 111 0.658
C2H4+ Ethylene cation 4 Au 84 -226 -310 -0.372
CHONH2 formamide 12 A" 289 -278 -567 -1.037
C10H8 naphthalene 28 B2g 461 -213 -674 -2.159
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 53 -22 1.427
CH3COOCH3 methyl acetate 27 A" 110 52 -58 2.116
C10H8 naphthalene 12 Au 581 455 -126 1.278
C10H8 naphthalene 27 B2g 770 418 -352 1.841
C9H8 Indene 40 A" 690 533 -157 1.295
C6H5CHO benzaldehyde 32 A" 688 495 -193 1.391
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.716
C6H5Cl chlorobenzene 18 B1 685 473 -212 1.448
C5H12 Pentane 23 A2 131 91 -40 1.444
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 143 -50 1.347
C5H8 Cyclopentene 18 A' 254 166 -88 1.530
C4H2 Diacetylene 7 Πg 482 193 -289 2.492
C2H3N3 1H-1,2,4-Triazole 18 A" 640 499 -141 1.284
NH2CN cyanamide 5 A' 408 685 277 0.595
CH3CCCH3 2-Butyne 16 E" 371 293 -78 1.266
HCNO fulminic acid 5 Π 224 171 -53 1.311
C3H6O Oxetane 18 B1 90 50 -40 1.798
HCCCl Chloroacetylene 5 Π 326 247 -79 1.321
NaOH sodium hydroxide 3 Π 300 216 -84 1.390
ZnO zinc monoxide 1 Σ 720 555 -165 1.297
ZnS Zinc sulfide 1 Σ 459 344 -115 1.335
C6H6 Benzvalene 10 A1 996 738 -258 1.349
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.677
H2CS- thioformaldehyde anion 4 B1 450 -99 -549 -4.533
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 328 -128 1.390
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
CH2OH Hydroxymethyl radical 9 A 234 432 198 0.541
HCCN cyanomethylene 5 Π 129 -389 -518 -0.331
C4H6 Methylenecyclopropane 17 B1 360 268 -92 1.344
CHCl2 dichloromethyl radical 4 A' 190 301 111 0.631
C2Cl2 dichloroacetylene 4 Πg 333 152 -181 2.190
ZnCl Zinc monochloride 1 Σ 391 298 -93 1.312
OClO- Chlorine dioxide anion 2 A1 418 309 -109 1.352
TiO Titanium monoxide 1 Σ 1009 3151 2142 0.320
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
C3 carbon trimer 3 Πu 63 38 -25 1.650
C4 Carbon tetramer 4 Πg 323 248 -75 1.303
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.559
Cl3- trichloride anion 2 Σu 327 186 -141 1.761
OPCl Phosphorus oxychloride 2 A' 308 468 160 0.658
OPCl Phosphorus oxychloride 3 A' 492 298 -194 1.651
H2POH Phosphinous acid 9 A" 375 257 -118 1.461
ZnCH3 Zinc monomethyl 6 E 315 592 277 0.532