多价态驱动生成多维碲基化合物材料的第一性原理预测

随着计算机技术和计算模拟方法的发展，理论结构预测在发现新材料方面发挥着越来越重要的作用。最近，人们在理论上成功预言了单元素二维碲烯，证明了Te元素的多价态特性（金属性和非金属性）是多种碲烯稳定存在的根本原因。这个特殊的多价态特性，尤其是金属性，也将会驱动Te元素与其他常见非金属元素（Se、S、C、N、P等）形成新型碲基化合物材料。基于这个猜想，本项目将致力于利用基于粒子群优化算法的CALYPSO和随机策略的RG2软件包，系统全面地从多维度、多元素、以及多比例角度对潜在新型碲基化合物材料进行结构预测，构造稳定性与关键物理参量的相图，探究元素多价特性驱动结构稳定的机制；并结合基于密度泛函理论的第一性原理计算和经典晶体生长理论，对潜在碲基化合物材料的结构和电子特性、高压相变以及初期成核生长机制进行描述和刻画。本项目的研究成果将为实验人员提供理论参考，加快实验发现新型碲基材料的进程。

Theoretical structure prediction has played an increasingly critical role in the discovery of new materials with the development of computer technology and computational simulation methods. Recently, people has successfully predicted two-dimensional elemental tellurene, and suggest that the stability of a variety of tellurene inherently arises from the multivalent nature of Te (metallic and non-metallic character). This particular multivalent nature, especially the metallic nature, will also drive Te to form new Te-based compound materials with other common non-metallic elements (Se, S, C, N, P, etc.). Based on this conjecture, this project will aim to use CALYPSO based on particle-swarm optimization algorithm and RG2 based on periodic graph theory and random strategy to systematically and comprehensively predict the structure of potential novel Te-based compound materials from multi-dimensional, multi-elemental and multi-proportion perspectives. And we will construct the phase diagram describing the structural stability in terms of key physical parameters to further explore the mechanism of structural stability driven by multivalent properties of elements. On the basis of density functional theory and classical crystal growth theory, we will study structural and electronic properties, high-pressure phase transition as well as initial nucleation and growth mechanism of potential Te-based materials. The research results of this project will provide theoretical reference for experimenters and accelerate the process of discovering new Te-based materials in experiments.