Errors in Intermolecular Interaction Energies for X40 set (kcal/mol)

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Errors in various methods, relative to Reference 
(all numbers in Kcalmol-1)
System CCSD(T)/CBS PM7       PM6      PM6-D3H4    PM6-D3H4X
01 Methane - F2 -0.5 0.78 0.88 0.57   0.57
02 Methane Cl2 -1.1 -0.63 0.10 -0.30 -0.30
03 Methane Br2 -1.3 0.84 -0.50 -0.84 -0.84
04 Methane I2 -1.3 0.82 -0.47 -0.78 -0.78
05 Fluoromethane methane -0.8 0.50 0.65 -0.07 -0.07
06 Chloromethane methane -1.0 -0.30 0.63 -0.26 -0.26
07 Trifluoromethane methane -0.7 0.22 0.70 -0.05 -0.05
08 Trichloromethane methane -1.1 -1.66 0.61 -0.63 -0.63
09 Fluoromethane dimer -1.6 1.17 1.57 1.11 1.11
10 Chloromethane dimer -1.3 -0.82 0.36 -0.12 -0.12
11 Trifluorobenzene benzene -4.4 -1.03 3.67 0.42 0.42
12 Hexafluorobenzene benzene -6.1 -0.56 4.68 1.15 1.15
13 Chloromethane formaldehyde -1.17 -0.21 0.67 0.39 0.46
14 Bromomethane formaldehyde -1.72 1.15 -0.20 -0.42 0.20
15 Iodomethane formaldehyde -2.38 4.71 -0.26 -0.45 0.22
16 Trifluorochloromethane formaldehyde -2.25 -0.11 0.38 0.08 0.54
17 Trifluorobromomethane formaldehyde -3.10 1.09 -0.61 -0.86 0.41
18 Trifluoroiodomethane formaldehyde -4.08 7.10 -1.63 -1.84 -0.14
19 Chlorobenzene acetone -1.49 -0.49 0.79 0.06 0.21
20 Bromobenzene acetone -2.43 0.86 -0.30 -0.99 -0.11
21 Iodobenzene acetone -3.46 3.46 -0.46 -1.07 0.08
22 Chlorobenzene trimethylamine -2.11 -1.14 1.45 0.43 0.50
23 Bromobenzene trimethylamine -3.78 -0.46 -5.79 -6.90 -0.14
24 Iodobenzene trimethylamine -5.81 5.34 0.14 -0.91 0.07
25 Bromobenzene methanethiol -2.32 0.49 2.14 1.63 1.63
26 Iodobenzene methanethiol -3.08 0.90 -0.85 -1.32 -0.03
27 Bromomethane benzene -1.81 -0.61 0.20 -0.81 -0.81
28 Iodomethane benzene -2.48 0.25 -0.04 -1.01 -1.01
29 Trifluorobromomethane benzene -3.11 -0.08 0.43 -0.54 -0.54
30 Trifluoroiodomethane benzene -3.92 1.03 -0.21 -1.12 -1.12
31 Trifluoromethanol water -9.67 0.32 3.48 1.08 1.08
32 Trichloromethanol water -10.41 -0.99 3.33 0.68 0.68
33 HF methanol -9.59 6.88 6.01 5.89 5.89
34 HCl methanol -6.30 0.65 0.58 0.22 0.43
35 HBr methanol -5.36 0.93 -0.12 -0.53 -0.15
36 HI methanol -3.97 -0.82 -0.73 -1.21 -1.04
37 HF methylamine -14.32 10.90 11.24 11.39 11.39
38 HCl methylamine -11.42 0.56 3.14 3.06 3.16
39 Methanol fluoromethane -3.89 5.90 5.10 4.65 4.65
40 Methanol chloromethane -3.78 1.32 1.82 1.28 1.28
             
RMSD: 2.897 2.795 2.590 2.304
MAD or AUE: 1.703 1.672 1.427 1.106
MAX: 10.899   11.243   11.387   11.387

 

Notes: Reference intermolecular interaction energies are taken from "Benchmark Calculations of Noncovalent Interactions of Halogenated Molecules" Řezáč, J., Riley, K.E., Hobza, P., J. Chem. Theory Comput. 8, 4285–4292 (2012), DOI: 10.1021/ct300647k  

PM6-D3H4X: Brahmkshatriya, P. S.; Dobeš, P.; Fanfrlík, J.; Řezáč, J.; Paruch, K.; Bronowska, A.; Lepšík, M.; Hobza, P. "Quantum Mechanical Scoring: Structural and Energetic Insights into Cyclin-Dependent Kinase 2 Inhibition by Pyrazolo[1,5-a]pyrimidines" Curr. Comput.-Aid. Drug. 2013, 9 (1), 118–129.

PM6: Stewart J. J. P., "Optimization of Parameters for Semiempirical Methods V: Modification of NDDO Approximations and Application to 70 Elements", J. Mol. Modeling 13, 1173:1213 (2007).

PM6-D3H4: Řezáč, J. and Hobza, P., "Advanced Corrections of Hydrogen Bonding and Dispersion for Semiempirical Quantum Mechanical Methods",   Journal of Chemical Theory and Computation, 2012 8 (1), 141-151 DOI: 10.1021/ct200751e.

PM7: Stewart J. J. P., "Optimization of Parameters for Semiempirical Methods VI: More Modifications to the NDDO Approximations and re-optimization of Parameters", J. Mol. Modeling 19, 1-32 (2013).

For a description of how errors were calculated, see Calculation of Error.