Calculating Heat of Formation Values of Energetic Compounds: A Comparative Study
Table 2
Statistical comparison of experimental gas-phase heat of formation values with values calculated using several theoretical approaches.
T1
(kcal/mol)
DFT Atomic and Group contribution
(kcal/mol)
DFT isodesmic
(kcal/mol)
Group Add.
(kcal/mol)
PM7
(kcal/mol)
RM1
(kcal/mol)
rms deviation
5.0
3.0
3.7
5.4 (3.4)
11.8 (6.0)
12.9 (5.9)
MAE
3.7
2.1
2.5
3.3 (2.5)
7.5 (4.9)
7.9 (4.8)
Max. Dev. (kcal/mol)
13.5
9.1
13.9
21.2 (9.6)
53.9 (13.2)
58.9 (12.6)
Number of values 2.0 kcal/mol
17
28
27
19
10
12
Number of values 3.0 kcal/mol
25
35
33
24
14
17
Number of values 4.0 kcal/mol
32
37
37
28
18
18
0.98728
0.9958
0.99277
0.9863 (0.99435)
0.92817 (0.98063)
0.91605 (0.98141)
Values in parentheses represent data in which values for compounds having deviations from experiment greater than 14.0 kcal/mol were omitted. See text for explanation.