In this work, we present a new vacancy model which proves that both lithium and tantalate (niobium) vacancies can coexist in the lattice structure of lithium tantalate and lithium niobate. Using the theoretical approach to the defect structure analysis, which is developed by Safaryan, a comparison between three defect models (tantalate/niobium vacancies, lithium vacancies, and mixed vacancies) has been proposed. The calculated values of the Curie temperature for different compositions of nonstoichiometric lithium tantalate and lithium niobite show that the mixed vacancy model can effectively describe the defect structure in nonstoichiometric lithium tantalate and lithium niobate. Also, it can reveal good correspondence with experimental results.

在这项工作中，我们提出了一个新的空位模型，该模型证明锂和钽酸（铌）空位都可以共存于钽酸锂和铌酸锂的晶格结构中。使用由萨法良（Safaryan）开发的理论方法进行缺陷结构分析，提出了三种缺陷模型（钽/铌空位，锂空位和混合空位）之间的比较。计算出的非化学计量的钽酸锂和铌酸锂的不同组成的居里温度值表明，混合空位模型可以有效地描述非化学计量的钽酸锂和铌酸锂的缺陷结构。而且，它可以揭示与实验结果的良好对应性。