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 PBEPBE/cc-pV(T+d)Z
Calculated values were scaled by 0.9926.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 183 70 0.619
C4H10O Ethoxy ethane 12 A1 240 186 -54 1.290
C4H10O Ethoxy ethane 20 A2 137 107 -30 1.275
C4H10O Ethoxy ethane 28 B1 126 102 -24 1.235
CH3CONH2 Acetamide 20 A 259 120 -139 2.153
CH3COOH Acetic acid 18 torsion A" 93 65 -28 1.435
CH3OH Methyl alcohol 12 torsion A" 200 302 102 0.662
C2H6O2S Dimethyl sulfone 20 B1 262 201 -61 1.301
CH2Cl2 Methylene chloride 1 A1 2999 270 -2729 11.094
CH2Cl2 Methylene chloride 2 A1 1467 689 -778 2.129
CH2Cl2 Methylene chloride 3 A1 717 1395 678 0.514
CH2Cl2 Methylene chloride 4 A1 282 3018 2736 0.093
CH2Cl2 Methylene chloride 6 B1 3040 866 -2174 3.512
CH2Cl2 Methylene chloride 7 B1 898 3090 2192 0.291
CH2Cl2 Methylene chloride 8 B2 1268 701 -567 1.810
CH2Cl2 Methylene chloride 9 B2 758 1226 468 0.618
CHONH2 formamide 12 torsion A" 289 190 -99 1.522
CH3OCHO methyl formate 18 torsion A" 130 103 -27 1.258
C5H8 Cyclopentene 18 torsion A' 254 136 -118 1.868
C4H4N2 Pyridazine 13 A2 421 345 -76 1.220
C5H12 Propane, 2,2-dimethyl- 12 T1 203 304 101 0.667
C2H3NO3 Oxamic acid 3 A' 2600 3472 872 0.749
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 16 A" 984 795 -189 1.238
C2H3NO3 Oxamic acid 17 A" 815 661 -154 1.234
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.497
C5H8 1,4-Pentadiene 16 A 137 289 152 0.473
CH3ONO Methyl nitrite 15 torsion A" 186 141 -45 1.319
C2F2 difluoroacetylene 4 Πg 270 202 -68 1.336
CH3OO methylperoxy radical 12 torsion A" 170 123 -47 1.387
CH2OH Hydroxymethyl radical 9 torsion A 234 414 180 0.565
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 871 -265 1.305
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 155 -109 1.708
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 102 -256 3.503
C3H3 Propargyl radical 7 B1 490 405 -85 1.211
C4H6 Methylenecyclopropane 17 B1 360 277 -83 1.299
N2O4 Dinitrogen tetroxide 9 B2u 265 193 -72 1.370
N2O3 Dinitrogen trioxide 9 torsion A" 63 134 71 0.472
NO3 Nitrogen trioxide 3 E' 1492 1221 -271 1.222
C4 Carbon tetramer 4 Πg 323 209 -114 1.549
S3 Sulfur trimer 2 A1 281 580 299 0.485
HSSSH trisulfane 5 A' 240 197 -43 1.215
BH3PH3 borane phosphine 12 E 447 367 -80 1.219
OPCl Phosphorus oxychloride 2 A' 308 478 170 0.644
OPCl Phosphorus oxychloride 3 A' 492 288 -204 1.710
H2POH Phosphinous acid 9 A" 375 250 -125 1.499
Mg2 Magnesium diatomic 1 Σg 48 101 53 0.475