Atomistic modeling of diffuse scattering in cubic PbZrO.sub.3./sub..

0454345 - FZÚ 2016 RIV GB eng J - Journal Article
Pasciak, Marek - Welberry, T.R. - Heerdegen, A.P. - Laguta, Valentyn - Ostapchuk, Tetyana - Leoni, S. - Hlinka, Jiří
Atomistic modeling of diffuse scattering in cubic PbZrO₃.
Phase Transitions. Roč. 88, č. 3 (2015), s. 273-282. ISSN 0141-1594. E-ISSN 1029-0338
R&D Projects: GA ČR GA13-15110S
Institutional support: RVO:68378271
Keywords : diffuse scattering * local structure * soft modes * anti-ferroelectricity * zirconates * molecular dynamics
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 0.858, year: 2015

We present a joint theoretical and experimental study on diffuse scattering in cubic PbZrO3. A comprehensive synchrotron data-set reveals 110-oriented diffuse streaks emanating from Bragg reflections and showing a strong intensity variation in the vicinity of selected $M$ points. The intensity distribution on the $hk1/2$ section reveals another system of weaker but much sharper $q 1/2 1/2$-type diffuse lines extended along 100 directions. These lines are slightly bent and intersect the 110-oriented diffuse streaks a little off the $M$ points of the Brillouin zone. Molecular dynamics simulations with an ab initio derived shell model allow one to assign observed diffuse intensity to correlations coming from different atomic species. It is shown that interactions between the Pb-related modes and the octahedra tilting modes are manifested in subtle diffuse scattering features.
Permanent Link: http://hdl.handle.net/11104/0255044