期刊
JOURNAL OF SOLID STATE CHEMISTRY
卷 167, 期 2, 页码 446-452出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1006/jssc.2002.9653
关键词
high pressure; phase transition; ferroelectric; perovskite
Synchrotron X-ray powder diffraction patterns were collected at the European Synchrotron Radiation Facility (ESRF, Grenoble, France) on powder, samples of PbTiO3 (tetragonal, Z = 1 P4mm a = 3.9036(1) Angstrom and c = 4.1440(2) Angstrom at room conditions) applying external pressure using a diamond anvil cell. Data were collected at four different temperatures (room temperature, 462, 538 and 623 K) up to the phase transition to the cubic phase (Z = 1, Pm3m a = 3.8647(4) Angstrom at RT and 11.6 GPa). Analyzing the behavior of the cell parameters obtained by the Rietveld refinement, we were able to extract the dependence of the critical temperature on external pressure. The bulk moduli of the lead titanate were calculated for the first time. The progressive decrease of the distortion of the Pb and Ti coordination polyhedra with pressure allows to propose a structural explanation of the first-/second-order cross-over in the ferroelectric-paralectric phase transition on applying pressure. (C) 2002 Elsevier Science (USA).
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据