A Novel BN Polymorph in P4/mbm Phase with a (4,4) Nanotube

Herein, based on density functional theory, a new boron nitride structure derived from diamond is designed, and its stability is also proved. The new boron nitride structure is denoted as P 4/ mbm BN. The elastic moduli (bulk modulus, shear modulus, and Young's modulus) of P 4/ mbm BN are slightly greater than those of C 72 and T carbon, and the shear modulus and Young's modulus are larger than those of P ‐4 m 2 B 7 N 7 , B 11 N 11 , and B 15 N 15 . The shear modulus and Young's modulus of P 4/ mbm BN exhibit a smaller mechanical anisotropy than that of P ‐4 m 2 B 7 N 7 , B 11 N 11 , and B 15 N 15 , where P ‐4 m 2 B 15 N 15 exhibits the greatest mechanical anisotropy of shear modulus and Young's modulus. The anisotropy of shear modulus in the (100), (010) plane of P ‐4 m 2 B 15 N 15 is 26.5 times that of P 4/ mbm BN, and the mechanical anisotropy of Young's modulus in (110) plane of P ‐4 m 2 B 15 N 15 is 35.6 times that of P 4/ mbm BN. P 4/ mbm BN is a wide and indirect bandgap semiconductor material with bandgap of 4.8 eV. Compared with silicon carbide and gallium nitride, P 4/ mbm BN has a wider bandgap, it might be more suitable for making high temperature, high frequency, radiation resistance, and high‐power devices.