Morphology prediction of 5,5'-bistetrazole-1,1'-diolate (BTO) crystal in solvents with different models using molecular dynamics simulation

Abstract For explaining in detail the influence of solvents on the morphology of 5,5'-bistetrazole-1,1'-diolate (BTO) crystal, molecular dynamics (MD) methods were used to simulate solution-crystal interface interactions, modified attachment energy (AE) model and occupancy model were used to predict the morphology of BTO. The simulation results demonstrated that the morphologically dominant growth surfaces of BTO in vacuum are (0 0 1), (1 1 0), (2 0 -1) and (2 0 0), respectively. There has many intramolecular and intermolecular interactions exist with different strength in the crystal of BTO, and the atomic system is dominated by N···H/H···N contacts which are comprising 60.2%. Analysis of the crystal bond chain and crystal packing further explained the mechanism of crystal surface growth. The size of the BTO crystal face-solvent model and the number of solvent molecules was designed. The morphologies of BTO in different solvents with three models were displayed. Results of comparing the BTO crystal relative surface/volume ratio in different solvents indicated that the Diethyl Ether (DEE) solvent is more favorable for the spheroidization of BTO crystal in the study.