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IV.A.4.a.

Isomerization sets

Comparison of sets of isomerization reactions

These sets of molecules are from the paper "Performance of B3LYP Density Functional Methods for a Large Set of Organic Molecules" by Julian Tirado-Rives and William L. Jorgenson, J. Chem. Theory Comput. 2008, 4, 297-306 Energies in kJ mol-1
original data displayed. press to display differences
differences displayed. press to display original data

hydrocarbons

Reaction enthalpies in kJ mol-1
reactant product Exp. (298.15K) HF/6-31G* HF/6-31+G** HF/cc-pVTZ B3LYP/6-31G* B3LYP/6-31+G** B3LYP/cc-pVTZ MP2/6-31G* MP2/6-31+G** MP2/cc-pVTZ reactant product
drawing of propyne drawing of allene 5.50 8.45 5.79 8.17 -11.56 -11.59 -7.83 20.16 15.73 19.66 CH3CCH CH2CCH2
drawing of propyne drawing of cyclopropene 91.60 108.35 111.09 113.63 89.87 93.78 99.75 95.99 94.87 100.07 CH3CCH C3H4
drawing of Propene drawing of Cyclopropane 33.60 33.10 37.80 40.51 32.44 35.41 37.35 18.30 20.08 20.92 CH2CHCH3 C3H6
drawing of 1,3-Butadiene drawing of Cyclobutene 47.50 39.88 62.60 50.96 34.72 57.85 48.71 32.74 31.55 38.81 CH2CHCHCH2 C4H6
drawing of 1-Propene, 2-methyl- drawing of 2-Butene, (E)- 5.30 0.68 1.87 1.83 1.00 1.32 1.16 3.72 4.93 5.51 CH2C(CH3)CH3 CH3CHCHCH3
drawing of 2-Butene, (E)- drawing of 1-Butene 12.00 11.35 9.14 9.98 15.33 13.14 13.46 12.42 9.51 10.66 CH3CHCHCH3 CH2CHCH2CH3
drawing of 2-Butene, (E)- drawing of 2-Butene, (Z)- 4.70 6.70 6.41 6.60 5.61 5.50 5.32 6.43 6.07 4.64 CH3CHCHCH3 CH3CHCHCH3
drawing of 1,3-Pentadiene, (E)- drawing of 1,4-Pentadiene 29.86 28.16 24.61 26.18 38.01 34.45 34.63 30.58 25.99 28.97 C5H8 C5H8
drawing of Cyclopentene drawing of Ethenylcyclopropane 97.30 97.48 90.47 89.95 92.84 85.89 83.13 98.47 90.35 93.90 C5H8 C5H8
drawing of Propane, 2,2-dimethyl- drawing of Pentane 21.10 1.89 2.81 0.91 3.43 4.53 3.17 19.42 20.85 19.95 C5H12 C5H12
drawing of toluene drawing of Norbornadiene 190.00 230.12 232.81 233.02 234.63 234.30 239.26 197.62   197.74 C6H5CH3 C7H8
drawing of Styrene drawing of cyclooctatetraene 150.70 160.81 158.96 156.87 169.92 165.88 164.24 174.28 169.42 175.30 C6H5CHCH2 C8H8
Mean Absolute Errors 32.99 (126) 7.95 (40) 10.81 (13) 10.57 (13) 10.31 (13) 11.43 (13) 8.11 (25) 5.75 (86) 7.67 (25)  

nitrogen-containing molecules

Reaction enthalpies in kJ mol-1
reactant product Exp. (298.15K) HF/6-31G* HF/6-31+G** HF/cc-pVTZ B3LYP/6-31G* B3LYP/6-31+G** B3LYP/cc-pVTZ MP2/6-31G* MP2/6-31+G** MP2/cc-pVTZ reactant product
drawing of Acetonitrile drawing of methyl isocyanide 99.10 87.09 80.44 84.07 100.70 93.59 99.28 119.07 109.72 113.43 CH3CN CH3NC
drawing of N-methylmethanimine drawing of Aziridine 82.00 60.20 55.20 55.47 60.23 53.77 52.73 48.89 44.04 36.29 CH2NCH3 C2H5N
drawing of Ethylamine drawing of Dimethylamine 28.90 23.00 30.77 30.28 20.69 29.65 30.20 26.87 33.34 34.47 CH3CH2NH2 CH3NHCH3
drawing of 1,3-Diazine drawing of Pyrazine 0.13 27.52 27.45 28.05 17.04 17.12 17.36 15.37 15.08 15.18 C4H4N2 C4H4N2
drawing of Pyrazine drawing of Pyridazine 82.30 86.58 86.26 84.78 77.84 77.24 76.44 76.95 77.64 76.84 C4H4N2 C4H4N2
Mean Absolute Errors 13.87 (39) 13.97 (16) 14.67 (5) 10.59 (5) 11.31 (5) 10.77 (5) 14.57 (12) 11.00 (31) 15.96 (12)  

oxygen-containing molecules

Reaction enthalpies in kJ mol-1
reactant product Exp. (298.15K) HF/6-31G* HF/6-31+G** HF/cc-pVTZ B3LYP/6-31G* B3LYP/6-31+G** B3LYP/cc-pVTZ MP2/6-31G* MP2/6-31+G** MP2/cc-pVTZ reactant product
drawing of Acetaldehyde drawing of Ethylene oxide 118.07 127.62 128.73 127.87 115.15 116.45 117.31 113.78 112.34 107.73 CH3CHO C2H4O
drawing of Ethanol drawing of Dimethyl ether 50.70 28.88 45.83 43.12 23.00 43.77 42.36 35.48 51.33 51.79 CH3CH2OH CH3OCH3
drawing of Acetic acid drawing of methyl formate 79.90 55.73 70.38 68.05 49.29 65.94 65.65 58.55 70.03 71.99 CH3COOH CH3OCHO
drawing of Acetone drawing of Oxetane 136.60 -80.29 141.25 142.77 133.05 136.80 140.16 138.01 138.36 131.59 CH3COCH3 C3H6O
drawing of 1,2-Ethanediol drawing of dimethylperoxide 261.50 245.92 284.22 277.51 195.82 239.33 236.78 227.75 264.75 269.94 C2H6O2 CH3OOCH3
drawing of Furan, tetrahydro- drawing of Ethene, ethoxy- 44.04 61.35 52.28 45.25 51.42 44.14 35.90 71.98 66.36 64.42 C4H8O C2H3OC2H5
Mean Absolute Errors 33.98 (54) 8.97 (22) 8.77 (6) 29.06 (7) 7.50 (6) 9.96 (6) 14.25 (16) 7.86 (48) 7.69 (19)