return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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 CCSD(T)/aug-cc-pVDZ
Calculated values were scaled by 0.9625.

Species Name mode Symmetry Experiment Theory difference ratio
HCOOH Formic acid 2 A' 2943 3583 640 0.821
HCOOH Formic acid 3 A' 1770 2980 1210 0.594
HCOOH Formic acid 4 A' 1387 2966 1579 0.468
HCOOH Formic acid 5 A' 1229 1775 546 0.693
HCOOH Formic acid 6 A' 1105 1710 605 0.646
HCOOH Formic acid 7 A' 625 1362 737 0.459
CH3OH Methyl alcohol 12 A" 200 298 98 0.671
C2H4+ Ethylene cation 4 Au 84 -268 -352 -0.314
C2H2 Acetylene 4 Πg 612 354 -258 1.728
CHONH2 formamide 12 A" 289 -45 -334 -6.426
CBr2F2 Methane, dibromodifluoro- 3 A1 140 329 189 0.426
CF2CCl2 difluorodichloroethylene 7 B1 1327 526 -801 2.523
CF2CCl2 difluorodichloroethylene 8 B1 989 298 -691 3.322
CF2CCl2 difluorodichloroethylene 11 B2 564 437 -127 1.291
CF2CCl2 difluorodichloroethylene 12 B2 323 174 -149 1.855
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 308 -901 3.921
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 391 -142 1.363
CH2NN diazomethane 6 B1 406 288 -118 1.409
C4H2 Diacetylene 7 Πg 482 -637 -1119 -0.757
C4H2 Diacetylene 8 Πu 630 481 -149 1.310
C4H2 Diacetylene 9 Πu 231 110 -121 2.102
C3H6O Oxetane 12 A2 986 789 -197 1.250
C3H6O Oxetane 18 B1 90 -79 -169 -1.139
C3H6O Oxetane 23 B2 1228 972 -256 1.264
HCNO fulminic acid 5 Π 224 -236 -461 -0.948
HCCCl Chloroacetylene 5 Π 326 233 -93 1.398
SiF2+ Silicon difluoride cation 2 A1 350 272 -78 1.288
GeH3CH3 methyl germane 4 A1 843 2914 2071 0.289
GeH3CH3 methyl germane 5 A1 602 2053 1451 0.293
GeH3CH3 methyl germane 8 E 2084 3002 918 0.694
GeH3CH3 methyl germane 9 E 1428 2050 622 0.696
GeH3CH3 methyl germane 10 E 900 1391 491 0.647
C2H Ethynyl radical 3 Π 372 -152 -524 -2.438
CH3 Methyl radical 2 A2" 606 480 -127 1.265
CH2OH Hydroxymethyl radical 9 A 234 413 179 0.566
CHCl2 dichloromethyl radical 4 A' 190 289 99 0.659
SF5 Sulfur pentafluoride 2 A1 633 475 -158 1.332
SF5 Sulfur pentafluoride 7 E 818 585 -233 1.397
SF5 Sulfur pentafluoride 9 E 387 307 -80 1.261
C3 carbon trimer 3 Πu 63 -167 -230 -0.380
SiH- silicon monohydride anion 1 Σ 2175 1737 -438 1.252
SF5Cl sulfur chloropentafluoride 5 B1 625 433 -192 1.442
SF5Cl sulfur chloropentafluoride 11 E 397 886 489 0.448
Cl3- trichloride anion 2 Σu 327 257 -70 1.271
H2OH2O water dimer 12 A" 88 126 38 0.698
F3- trifluoride anion 1 Σg 461 366 -95 1.260
H2POH Phosphinous acid 9 A" 375 246 -130 1.528
Mg2 Magnesium diatomic 1 Σg 51 24 -27 2.161
CH3BO Borane, methyloxo- 7 E 897 1388 491 0.646