【摘 要】
：
Generally, most materials expand when heated and contract when cooled, whereas negative thermal expansion (NTE) materials are very rare. As a typical NTE material, PbTiO3 and related compounds have drawn particular interest in recent years. The discovery
【机 构】
：
Beijing Advanced Innovation Center for Materials Genome Engineering,Institute of Solid State Chemist
论文部分内容阅读
Generally, most materials expand when heated and contract when cooled, whereas negative thermal expansion (NTE) materials are very rare. As a typical NTE material, PbTiO3 and related compounds have drawn particular interest in recent years. The discovery of an en-hanced NTE system in PbTiO3 is beneficial to deepen our understanding of its mechanism and regulate its properties. At present, the method of discriminating an enhanced NTE material based on PbTiO3 is not universal. Here, we propose a semi-empirical method through evaluating the average lattice distortion in related systems to estimate the relative coefficient of thermal expansion conveniently. The rationality of the method was verified by the analysis of the 0.6PbTiO3–0.4Bi(Ga xFe1?x)O3 system. So far, all PbTiO3-based compounds with enhanced NTE conform well to this method. This method provides the possibility to find more enhanced NTE PbTiO3-based materials.
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