Dear all,
I tried the reaxff for CHO (Chenoweth et al., JPCA, 2008) using lammps-17Nov16 and lammps-11May18, but failed to reproduce some of the reaction energies presented in the supporting information of this paper (Chenoweth et al., JPCA, 2008).
https://pubs.acs.org.ccindex.cn/doi/suppl/10.1021/jp709896w/suppl_file/jp709896w-file003.pdf
My results V.S. Chenoweth’s are compared in the following table (in kcal/mol), where you can see a big difference for two reactions.
Chenoweth et al
My test
Reaction
Reaxff
QM
Reaxff
CH3CH2CH2CH3 → CCCC + 5H2
149.7
150.2
355.6
CH3CH2CH2OH → CH3CH2CHO + H2
47.2
21.0
52.2
CH3CH2CHO → CH3CHCO +H2
41.6
30.2
40.7
CH3CHCO → CH2CCO + H2
92.7
80.4
50.6
H2CCH2 → H2C + CH2
173.7
178.8
173.7
I tried other initial structures, but it did not change. The input files I used for the first reaction are included in the attachment.
Can anyone give me some advice on this problem?
Best regards,
Yingchun
dehydrogenation-1.tar.gz (4.08 KB)