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 B1B95/CEP-31G*
Calculated values were scaled by 0.9572.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 174 61 0.650
C4H10O Ethoxy ethane 12 A1 240 180 -60 1.335
C4H10O Ethoxy ethane 20 A2 137 102 -35 1.339
CH3CONH2 Acetamide 20 A 259 117 -142 2.209
CH3OH Methyl alcohol 12 torsion A" 200 330 130 0.606
CH3COCH3 Acetone 12 torsion A2 77 26 -51 2.959
C2H6O2S Dimethyl sulfone 20 B1 262 198 -64 1.321
CHONH2 formamide 12 torsion A" 289 106 -183 2.722
CH3COCl Acetyl Chloride 15 torsion A" 166 129 -37 1.289
CH3COOCH3 methyl acetate 27 torsion A" 110 37 -73 3.007
CH3OCHO methyl formate 18 torsion A" 130 201 71 0.647
C4H8S Thiophene, tetrahydro- 5 A 1464 2964 1500 0.494
C4H8S Thiophene, tetrahydro- 6 A 1441 2964 1523 0.486
C4H8S Thiophene, tetrahydro- 7 A 1321 2954 1633 0.447
C4H8S Thiophene, tetrahydro- 8 A 1276 2949 1673 0.433
C4H8S Thiophene, tetrahydro- 12 A 888 1410 522 0.630
C4H8S Thiophene, tetrahydro- 13 A 829 1300 471 0.638
C4H8S Thiophene, tetrahydro- 14 A 822 1268 446 0.648
C4H8S Thiophene, tetrahydro- 15 A 678 1247 569 0.544
C4H8S Thiophene, tetrahydro- 16 A 472 1221 749 0.387
C4H8S Thiophene, tetrahydro- 17 A 290 1174 884 0.247
C5H8 Cyclopentene 18 torsion A' 254 188 -66 1.349
C5H8 Spiropentane 8 A2 919 687 -232 1.337
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.679
C2H3NO3 Oxamic acid 3 A' 2600 3473 873 0.749
C2H3NO3 Oxamic acid 15 A' 328 246 -82 1.336
C2H3NO3 Oxamic acid 17 A" 815 645 -170 1.263
C2H3NO3 Oxamic acid 21 A" 162 62 -100 2.599
CH3CCCH3 2-Butyne 16 E" 371 289 -82 1.282
C3O2 Carbon suboxide 7 Πu 61 181 120 0.337
C5H8 1,4-Pentadiene 16 A 137 278 141 0.492
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 176 -51 1.291
CH3SSCH3 Disulfide, dimethyl 13 torsion A 117 73 -44 1.610
C2F2 difluoroacetylene 4 Πg 270 18 -252 14.611
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 131 -39 1.301
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 220 76 0.654
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 335 -121 1.361
C2H5 Ethyl radical 9 A' 528 58 -470 9.117
CH3 Methyl radical 2 torsion A2" 606 432 -174 1.403
CH2OH Hydroxymethyl radical 9 torsion A 234 442 208 0.530
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 856 -280 1.328
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 162 -102 1.629
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 106 -252 3.371
H2CCCCH2 Butatriene 16 B3g 330 152 -178 2.167
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.270
PCl5 Phosphorus pentachloride 7 E' 100 79 -21 1.259
N2O3 Dinitrogen trioxide 9 torsion A" 63 128 65 0.494
NO3 Nitrogen trioxide 3 E' 1492 1153 -339 1.294
NO3 Nitrogen trioxide 4 E' 360 206 -154 1.746
C3 carbon trimer 3 Πu 63 272 208 0.233
C4 Carbon tetramer 4 Πg 323 503 180 0.643
ClOO chloroperoxy radical 2 A' 414 282 -132 1.469
ClOO chloroperoxy radical 3 A' 201 93 -108 2.154
Mg2 Magnesium diatomic 1 Σg 48 72 24 0.667