return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

19 02 11 15 45

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 MP2/cc-pV(T+d)Z
Calculated values were scaled by 0.9525.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C4H10O Ethoxy ethane 12 A1 240 184 -56 1.305
C4H10O Ethoxy ethane 20 A2 137 94 -43 1.464
CH3COOH Acetic acid 18 torsion A" 93 73 -20 1.267
CH3OH Methyl alcohol 12 torsion A" 200 295 95 0.679
HCN+ hydrogen cyanide cation 1 Σ 3050 3582 532 0.851
HCN+ hydrogen cyanide cation 2 Σ 1800 2725 925 0.660
CH2Cl2 Methylene chloride 1 A1 2999 276 -2723 10.866
CH2Cl2 Methylene chloride 2 A1 1467 707 -760 2.076
CH2Cl2 Methylene chloride 3 A1 717 1413 696 0.507
CH2Cl2 Methylene chloride 4 A1 282 3005 2723 0.094
CH2Cl2 Methylene chloride 6 B1 3040 874 -2166 3.479
CH2Cl2 Methylene chloride 7 B1 898 3082 2184 0.291
CH2Cl2 Methylene chloride 8 B2 1268 760 -508 1.669
CH2Cl2 Methylene chloride 9 B2 758 1241 483 0.611
CH3COOCH3 methyl acetate 27 torsion A" 110 42 -68 2.613
C5H8 Cyclopentene 18 torsion A' 254 172 -82 1.473
CH2NN diazomethane 6 B1 406 109 -297 3.710
C2H3NO3 Oxamic acid 3 A' 2600 3455 855 0.753
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.269
C2H3NO3 Oxamic acid 17 A" 815 644 -171 1.265
C2H3NO3 Oxamic acid 21 A" 162 60 -102 2.687
C5H8 1,4-Pentadiene 16 A 137 289 152 0.474
CO+ carbon monoxide cation 1 Σ 2184 2737 554 0.798
NaOH sodium hydroxide 3 torsion Π 300 213 -87 1.410
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.345
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 123 -48 1.387
CN Cyano radical 1 Σ 2042 2758 716 0.741
C2H Ethynyl radical 2 Σ 1841 2400 559 0.767
C2H Ethynyl radical 3 torsion Π 372 781 409 0.476
CH3OO methylperoxy radical 12 torsion A" 170 123 -47 1.379
CH3 Methyl radical 2 torsion A2" 606 459 -148 1.322
CH2OH Hydroxymethyl radical 9 torsion A 234 419 185 0.559
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.346
O2+ diatomic oxygen cation 1 Σg 1873 1421 -452 1.318
O3 Ozone 3 B2 1042 2135 1093 0.488
OClO Chlorine dioxide 3 B2 1110 1705 595 0.651
NO Nitric oxide 1 Σ 1876 3184 1308 0.589
NO2 Nitrogen dioxide 3 B2 1618 4022 2404 0.402
N2O4 Dinitrogen tetroxide 9 B2u 265 194 -71 1.367
N2O3 Dinitrogen trioxide 9 torsion A" 63 160 97 0.393
NO3 Nitrogen trioxide 3 E' 1492 2283 791 0.654
NO3 Nitrogen trioxide 4 E' 360 702 342 0.513
C3 carbon trimer 3 Πu 63 164 101 0.386
SiP Silicon monophosphide 1 Σ 611 1023 412 0.597
AlO Aluminum monoxide 1 Σ 965 583 -383 1.657
FOO Dioxygen monofluoride radical 1 A' 1487 2684 1197 0.554
FOO Dioxygen monofluoride radical 2 A' 579 1247 668 0.464
FOO Dioxygen monofluoride radical 3 A' 376 652 276 0.577
OPCl Phosphorus oxychloride 2 A' 308 485 177 0.635
OPCl Phosphorus oxychloride 3 A' 492 293 -199 1.681
H2POH Phosphinous acid 9 A" 375 264 -111 1.421
SNO Nitrogen oxide sulfide 3 A' 792 512 -280 1.547
NSO sulfinyl amidogen 3 A' 300 125 -175 2.392