Results from DFT calculations are in many cases equivalent to experimental data. They describe a set of properties of a phase at a well-defined composition and temperature, T, most often at 0 K. In order to be practically useful in materials design, such data must be fitted to a thermodynamic model for the phase to allow interpolations and extrapolations. The intention of this paper is to give a summary of the state of the art by using the Calphad technique to model thermodynamic properties and calculate phase diagrams, including some models that should be avoided. Calphad models can decribe long range ordering (LRO) using sublattices and there are model parameters that can approximate short range ordering (SRO) within the experimental uncertainty. In addition to the DFT data, there is a need for experimental data, in particular, for the phase diagram, to determine the model parameters. Very small differences in Gibbs energy of the phases, far smaller than the uncertainties in the DFT calculations, determine the set of stable phases at varying composition and T. Thus, adjustment of the DFT results is often needed in order to obtain the correct set of stable phases.

中文翻译：

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从头算数据对LRO和SRO进行Calphad建模

DFT计算的结果在许多情况下等于实验数据。他们描述了在明确定义的成分和温度T下的相的一组特性，最常用的是0K。为了在材料设计中实际有用，必须将此类数据拟合到该相的热力学模型中，以允许进行内插和外推。本文旨在通过使用Calphad技术对热力学性质进行建模并计算相图（包括一些应避免的模型）来提供最新技术的概述。Calphad模型可以使用子晶格描述长距离排序（LRO），并且模型参数可以在实验不确定性范围内近似短距离排序（SRO）。除了DFT数据外，还需要实验数据（尤其是相图）来确定模型参数。相的吉布斯能量差异很小，远小于DFT计算中的不确定性，Ť。因此，经常需要调整DFT结果以获取正确的一组稳定相位。