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可靠而准确的稳定性第一性原理计算对材料的合成、反应性和性质的研究至关重要，对于探索新的化学空间和难以观察的相结构来说也很重要。稳定性涉及化学稳定能力（不同化学环境中化学计量组成保持不变的能力）和结构选择（一定化学计量组成的晶体结构取向）两个方面，对于已知材料，可用实验测量生成焓来预测。然而对于新材料和化学组成相同而空间结构不同的材料来说，则不可能或难以用实测生成焓来预测。来自美国的华裔科学家Haowei Peng 和 Jianwei Sun，应用密度泛函理论结合最近开发的强约束-适当规范（strongly constrained and appropriately normed, SCAN）泛函，对材料稳定问题的两个方面（化学稳定能力&结构选择）作了研究，发现该方法能对主要化合物群组的稳定性作可信的、有效的预测，而对过渡金属化合物稳定性预测，虽有进展，但仍是一个挑战。他们认为，SCAN函数为元素周期表的重要部分提供了一个稳健的模型，为新材料的开发和精细相变研究提供了良方。该文近期发表于npj Computational Materials 4: 9 (2018);  doi:10.1038/s41524-018-0065-z。英文标题与摘要如下，点击阅读原文可以自由获取论文PDF。

Efficient first-principles prediction of solid stability: Towards chemical accuracy

Yubo Zhang, Daniil A. Kitchaev, Julia Yang, Tina Chen, Stephen T. Dacek, Rafael A. Sarmiento-Pérez, Maguel A. L. Marques, Haowei Peng, Gerbrand Ceder, John P. Perdew & Jianwei Sun

Abstract  The question of material stability is of fundamental importance to any analysis of system properties in condensed matter physics and materials science. The ability to evaluate chemical stability, i.e., whether a stoichiometry will persist in some chemical environment, and structure selection, i.e. what crystal structure a stoichiometry will adopt, is critical to the prediction of materials synthesis, reactivity and properties. Here, we demonstrate that density functional theory, with the recently developed strongly constrained and appropriately normed (SCAN) functional, has advanced to a point where both facets of the stability problem can be reliably and efficiently predicted for main group compounds, while transition metal compounds are improved but remain a challenge. SCAN therefore offers a robust model for a significant portion of the periodic table, presenting an opportunity for the development of novel materials and the study of fine phase transformations even in largely unexplored systems with little to no experimental data.

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