Space group and crystal structure of the Perovskite CaTiO3 from 296 to 1720K

被引：180

作者：

Ali, R ^{[1
]}

Yashima, M ^{[1
]}

机构：

[1] Tokyo Inst Technol, Interdisciplinary Grad Sch Sci & Engn, Dept Mat Sci & Engn, Midori Ku, Yokohama, Kanagawa 2268502, Japan

来源：

JOURNAL OF SOLID STATE CHEMISTRY | 2005年 / 178卷 / 09期

关键词：

crystal structure; Rietveld method; phase transition; in situ measurements;

D O I：

10.1016/j.jssc.2005.06.027

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The structural phase transitions of the calcium titanate perovskite CaTiO3 were investigated by the Rietveld analysis of high-temperature neutron and X-ray powder diffraction data in the temperature range of 296-1720K. The present work demonstrates that the compound exhibits two reversible phase transitions of orthorhombic Pbnm-tetragonal I4/mcm and of I4/mcm\-cubic Pm (3) over barm at 1498 +/- 25 K and 1634 +/- 13 K, respectively. No evidence of Cmcm phase is observed between the Pbnm and I4/mcm structures. The lattice parameters discontinuously change at the Pbnm-I4/mcm transition point, while a continuous change is observed for the 14/mcm-Pm (3) over barm transformation. These results indicate that the Pbnm-I4/mcm transition is of first order and that the I4/mcm-Pm (3) over barm transformation is of either second or higher order. (c) 2005 Elsevier Inc. All rights reserved.

引用

页码：2867 / 2872

页数：6

共 25 条

[21] THE HIGH-TEMPERATURE PHASE-TRANSITION IN PEROVSKITE [J].