title: Body-centered tetragonal B2N2: a novel sp3 bonding boron nitride polymorph.
abstract: A novel polymorph of boron nitride (BN) with a body-centered tetragonal structure (bct-BN) has been predicted using first-principles calculations. The structural, vibrational, and mechanical calculations indicated that bct-BN is mechanically stable at zero pressure. When pressure is above 6 GPa, bct-BN becomes energetically more stable than h-BN. The bct-BN appears to be an intermediate phase between h-BN and w-BN due to a low energy barrier from h-BN to w-BN via bct-BN. Our results also indicated that the structure of unknown E-BN phase might be bct-BN.
authors.affiliation: State Key Laboratory of Metastable Materials, Science and Technology, Yanshan University, Qinhuangdao 066004, China. wenbin@ysu.edu.cn
authors.forename: Bin
authors.initials: B
authors.lastname: Wen
authors.forename: Jijun
authors.initials: J
authors.lastname: Zhao
authors.forename: Roderick
authors.initials: R
authors.lastname: Melnik
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Tian