Structure, Phase Transition, and Electronic Properties of K1−xNaxNbO3 Solid Solutions from First‐Principles Theory. Issue 12 (22nd August 2014)

• Record Type: Journal Article
• Authors: Liu, Shi‐Yu; Liu, Shiyang; Li, De‐Jun; Shen, Yaogen; Dang, Hongli; Liu, Yingdi; Xue, Wenhua; Wang, Sanwu; Sinnott, S. B.
• Is Part Of: Journal of the American Ceramic Society. Volume 97:Issue 12(2014)
• Page Start: 4019
• Page End: 4023
• Publication Date: 2014-08-22
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.13188
• Languages: English
• ISSNs: 0002-7820

Abstract

<abstract abstract-type="main" id="jace13188-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>With extensive first‐principles calculations, we investigated the geometric structure, phase transition, and electronic properties of orthorhombic, monoclinic, and tetragonal K_{1<italic>−x</italic>}Na_{<italic>x</italic>}NbO₃ (KNN) as functions of the Na content. We found that KNN undergoes an orthorhombic‐to‐monoclinic‐to‐orthorhombic phase transition when the Na content is gradually increased. We also found that the polarization vector of the monoclinic phase can be rotated more easily than those of the orthorhombic and tetragonal phases, giving rise to an enhanced piezoelectric response of the monoclinic KNN. Furthermore, our calculations provide an interpretation for the experimentally observed unusual broad peak of the KNN piezoelectric parameters.</p> </abstract>