Solvent effect on the crystal morphology of 2,6-diamino-3,5-dinitropyridine-1-oxide: a molecular dynamics simulation study.
The attachment energy (AE) calculations were performed to predict the growth morphology of 2,6-diamino-3,5-dinitropyridine-1-oxide (ANPyO) in vacuum. The molecular dynamics (MD) method was applied to simulate the interaction of trifluoroacetic acid solvent with the habit faces and the corrected AE model was adopted to predict the growth habit of ANPyO in the solvent. The results indicate that the growth morphology of ANPyO in vacuum is dominated by (110), (100), (10-1) and (11-2) faces. The corrected AE energies change in the order of (110)>(10-1)>(11-2)>(100), which causes the crystal morphology to become very close to a flake in trifluoroacetic acid solvent and accords well with the results obtained from experiments. The radial distribution function analysis shows that the solvent molecules adsorb on the ANPyO faces mainly via the solvent-crystal face interactions of hydrogen bonds, Coulomb and Van der Waals forces. In addition to the above results, the analysis of diffusion coefficient of trifluoroacetic acid molecules on the crystal growth faces shows that the growth habit is also affected by the diffusion capacity of trifluoroacetic acid molecules. These suggestions may be useful for the formulation design of ANPyO.
Department of Chemistry, Nanjing University of Science & Technology, Nanjing 210094, PR China; School of Chemical and Biological Engineering, Yancheng Institute of Technology, 9 Yingbin Avenue, Yancheng 224051, PR China.
Wenyan
W
Shi
Department of Chemistry, Nanjing University of Science & Technology, Nanjing 210094, PR China. Electronic address: waterswy@126.com.
Mingzhu
M
Xia
Department of Chemistry, Nanjing University of Science & Technology, Nanjing 210094, PR China.
Wu
W
Lei
Department of Chemistry, Nanjing University of Science & Technology, Nanjing 210094, PR China.
Fengyun
F
Wang
D006860:Hydrogen Bonding; D056004:Molecular Dynamics Simulation; D009930:Organic Chemicals / Q000737:chemistry*; D011487:Protein Conformation; D012997:Solvents / Q000737:chemistry*; D013816:Thermodynamics
D009930:Organic Chemicals; D012997:Solvents
2,6-Diamino-3,5-dinitropyridine-1-oxide; Crystal morphology; Molecular dynamics simulation; Self-diffusion coefficient; The attachment energy model