Detail publikace

On energetics of allotrope transformations in transition-metal diborides via plane-by-plane shearing

LEINER, T. KOUTNÁ, N. JANOVEC, J. ZELENÝ, M. MAYRHOFER, P. HOLEC, D.

Anglický název

On energetics of allotrope transformations in transition-metal diborides via plane-by-plane shearing

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

en

Originální abstrakt

Transition metal diborides crystallize in the a, y, or w type structure, in which pure transition metal layers alternate with pure boron layers stacked along the hexagonal [0001] axis. Here we view the prototypes as different stackings of the transition metal planes and suppose they can transform from one into another by a displacive transformation. Employing first-principles calculations, we simulate sliding of individual planes in the group IV-VII transition metal diborides along a transformation pathway connecting the a, y, and w structure. Chemistry-related trends are predicted in terms of energetic and structural changes along a transformation pathway, together with the mechanical and dynamical stability of the different stackings. Our results suggest that MnB2 and MoB2 possess the overall lowest sliding barriers among the investigated TMB2s. Furthermore, we discuss trends in strength and ductility indicators, including Young's modulus or Cauchy pressure, derived from elastic constants.

Anglický abstrakt

Transition metal diborides crystallize in the a, y, or w type structure, in which pure transition metal layers alternate with pure boron layers stacked along the hexagonal [0001] axis. Here we view the prototypes as different stackings of the transition metal planes and suppose they can transform from one into another by a displacive transformation. Employing first-principles calculations, we simulate sliding of individual planes in the group IV-VII transition metal diborides along a transformation pathway connecting the a, y, and w structure. Chemistry-related trends are predicted in terms of energetic and structural changes along a transformation pathway, together with the mechanical and dynamical stability of the different stackings. Our results suggest that MnB2 and MoB2 possess the overall lowest sliding barriers among the investigated TMB2s. Furthermore, we discuss trends in strength and ductility indicators, including Young's modulus or Cauchy pressure, derived from elastic constants.

Klíčová slova anglicky

Ab initio calculations; Transition metal diborides; Shear; Stacking sequence; Phase stability

Vydáno

29.06.2023

Nakladatel

Elsevier

Místo

OXFORD

ISSN

1879-2715

Ročník

215

Číslo

1

Strany od–do

112329–-

Počet stran

9

BIBTEX


@article{BUT184357,
  author="Thomas {Leiner} and Nikola {Koutná} and Jozef {Janovec} and Martin {Zelený} and Paul {Mayrhofer} and David {Holec},
  title="On energetics of allotrope transformations in transition-metal diborides via plane-by-plane shearing",
  year="2023",
  volume="215",
  number="1",
  month="June",
  pages="112329---",
  publisher="Elsevier",
  address="OXFORD",
  issn="1879-2715"
}