Crystal structures and decomposing of B–P compounds under pressure**Project supported by the National Natural Science Foundation of China (Grant Nos. 51632002, 51572108, 11634004, 11174102, and 11774119), the Program for Changjiang Scholars and Innovative Research Team in University, China (Grant No. IRT_15R23), the National Found for Fostering Talents of Basic Science, China (Grant No. J1103202), the National Key Research and Development

Abstract

We have systematically studied the structures, electronic properties, and lattice dynamics of B–P compounds at high pressures. BP and B6P are found to be thermodynamically stable below 100 GPa, and other stoichiometries are decomposable under pressure. The predicted structures of F-43m BP and R-3m B6P are in good agreement with the experimental results by comparing the powder diffraction file (PDF) standard cards with our simulated x-ray diffractions. The bonding properties of BP and B6P have also been analyzed by electronic localization functions, charge density difference, and Bader charge analysis. Our results show that BP and B6P decompose into B and P under high pressure, which is proven to be dominated by the volumes of them. Furthermore, the infrared and Raman spectra of F-43m and R-3m are investigated at selected pressures and will provide useful information for future experimental studies about B–P compounds.