Lattice dynamics and thermal properties of SrHfO3 by first-principles calculations

Hidenobu Murata, Tomoyuki Yamamoto, Hiroki Moriwake, Isao Tanaka

研究成果: Article査読

7 被引用数 (Scopus)

抄録

First-principles lattice dynamics calculations are systematically made on four polymorphs of SrHfO3. The hierarchy of the total energy at the ground state is Pm3m > I4/mcm > Cmcm > Pnma, which agrees with the sequence of iterative transitions with temperature as reported by experiments. Three structures, Pm3m, I4/mcm and Cmcm, are found to be dynamically unstable at the ground state. A soft mode of phonons appears in I4/mcm and Cmcm at the Γ-point. The atomic displacements for the soft mode are analogous to those of the R25 mode of Pm3m, which is related to the rotation of the HfO6 octahedron. Pnma phase shows lowest energy and it is the only dynamically stable structure among the four phases. The volume expansion coefficient, bulk modulus and heat capacity are computed within quasi-harmonic approximations using the vibrational density of states. They are compared to experimental data.

本文言語English
ページ(範囲)1628-1633
ページ数6
ジャーナルPhysica Status Solidi (B) Basic Research
246
7
DOI
出版ステータスPublished - 2009 7

ASJC Scopus subject areas

  • 電子材料、光学材料、および磁性材料
  • 凝縮系物理学

フィンガープリント

「Lattice dynamics and thermal properties of SrHfO<sub>3</sub> by first-principles calculations」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル