In:
Chinese Physics B, IOP Publishing, Vol. 28, No. 9 ( 2019-09-01), p. 096201-
Kurzfassung:
Via structural searching methodology and first-principles calculations, we predicted two new BC 6 N allotropes, a C-centered monoclinic BC 6 N (Cm-BC 6 N) and a primitive-centered monoclinic BC 6 N (Pm-BC 6 N). The lattice vibrations, elastic properties, ideal strength, theoretical hardness, and electronic structure of the predicted BC 6 N were investigated systematically. Our results reveal that Cm-BC 6 N is more favorable energetically than graphite-like g-BC 6 N above 20.6 GPa, which is lower than the transition pressures of r-BC 6 N, t-BC 6 N, and Pm-BC 6 N. Both Cm-BC 6 N and Pm-BC 6 N are indirect semiconductors with band gaps of 2.66 eV and 0.36 eV, respectively. Cm-BC 6 N exhibits the excellent ideal shear strength of 53.9 GPa in (011)[01 1 ¯ ], much greater than that of Pm-BC 6 N (25.0 GPa in (010)[101] shear direction), and Cm-BC 6 N shows a much lower anisotropy in shear strength than Pm-BC 6 N. The Vickers hardness of Cm-BC 6 N is estimated to be above 80 GPa, which is more outstanding than those of t-BC 6 N and r-BC 6 N.
Materialart:
Online-Ressource
ISSN:
1674-1056
DOI:
10.1088/1674-1056/ab3439
Sprache:
Unbekannt
Verlag:
IOP Publishing
Publikationsdatum:
2019
ZDB Id:
2412147-2
