In this work, we present the program MAELAS to calculate magnetocrystalline anisotropy energy, anisotropic magnetostrictive coefficients and magnetoelastic constants in an automated way by Density Functional Theory calculations. The program is based on the length optimization of the unit cell proposed by Wu and Freeman to calculate the magnetostrictive coefficients for cubic crystals. In addition to cubic crystals, this method is also implemented and generalized for other types of crystals that may be of interest in the study of magnetostrictive materials. As a benchmark, some tests are shown for well-known magnetic materials.

Program summary

Program Title: MAELAS

CPC Library link to program files: https://doi.org/10.17632/gxcdg3z7t6.1

Developer’s repository link: https://github.com/pnieves2019/MAELAS

Code Ocean capsule: https://codeocean.com/capsule/0361425

Licensing provisions: BSD 3-clause

Programming language: Python3

Nature of problem: To calculate anisotropic magnetostrictive coefficients and magnetoelastic constants in an automated way based on Density Functional Theory methods.

Solution method: In the first stage, the unit cell is relaxed through a spin-polarized calculation without spin-orbit coupling. Next, after a crystal symmetry analysis, a set of deformed lattice and spin configurations are generated using the pymatgen library [1]. The energy of these states is calculated by the first-principles code VASP [3], including the spin-orbit coupling. The anisotropic magnetostrictive coefficients are derived from the fitting of these energies to a quadratic polynomial [2]. Finally, if the elastic tensor is provided [4], then the magnetoelastic constants are also calculated.

Additional comments including restrictions and unusual features: This version supports the following crystal systems: Cubic (point groups 432, $\bar{4}3m$, $m\bar{3}m$), Hexagonal ($6mm$, 622, $\bar{6}2m$, $6∕mmm$), Trigonal (32, $3m$, $\bar{3}m$), Tetragonal ($4mm$, 422, $\bar{4}2m$, $4∕mmm$) and Orthorhombic (222, $2mm$, $mmm$).

References:

[1] S. P. Ong, W. D. Richards, A. Jain, G. Hautier, M. Kocher, S. Cholia, D. Gunter, V. L. Chevrier, K. A. Persson, and G. Ceder, Comput. Mater. Sci. 68, 314 (2013).

[2] R. Wu, A. J. Freeman, Journal of Applied Physics 79, 6209–6212 (1996).

[3] G. Kresse, J. Furthmüller, Phys. Rev. B 54 (1996) 11169.

[4] S. Zhang and R. Zhang, Comput. Phys. Commun. 220, 403 (2017).

中文翻译：

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MAELAS：通过计算高通量方法计算MAgneto-ELAStic属性

在这项工作中，我们提出了程序MAELAS通过密度泛函理论计算以自动方式计算磁晶各向异性能，各向异性磁致伸缩系数和磁弹性常数。该程序基于Wu和Freeman提出的单位晶胞的长度优化，以计算立方晶体的磁致伸缩系数。除立方晶体外，该方法也可用于磁致伸缩材料研究中可能感兴趣的其他类型的晶体。作为基准，显示了一些对知名磁性材料的测试。

计划摘要

节目名称： MAELAS

CPC库链接到程序文件：https://doi.org/10.17632/gxcdg3z7t6.1

开发人员的资料库链接： https : //github.com/pnieves2019/MAELAS

Code Ocean太空舱：https://codeocean.com/capsule/0361425

许可条款： BSD 3条款

编程语言： Python3

问题的性质：基于密度泛函理论方法自动计算各向异性磁致伸缩系数和磁弹性常数。

解决方法：在第一阶段，通过自旋极化计算来放松晶胞，而无需自旋轨道耦合。接下来，在进行晶体对称性分析之后，使用pymatgen库[1]生成了一组变形的晶格和自旋构型。这些状态的能量由第一原理代码VASP [3]计算，包括自旋轨道耦合。各向异性磁致伸缩系数是根据这些能量与二次多项式的拟合得出的[2]。最后，如果提供了弹性张量[4]，那么还将计算磁弹性常数。

其他注释，包括限制和不寻常的功能：此版本支持以下晶体系统：立方（点组432，$\bar{4}3米$， $米\bar{3}米$），六角形（$6米米$622 $\bar{6}\mathrm{2个}米$， $6∕米米米$），三角（32， $3米$， $\bar{3}米$），四角形（$4米米$422 $\bar{4}\mathrm{2个}米$， $4∕米米米$）和正交晶（222， $\mathrm{2个}米米$， $米米米$）。

参考：

[1] SP Ong，WD Richards，A。Jain，G。Hautier，M。Kocher，S。Cholia，D。Gunter，VL ​​Chevrier，KA Persson和G. Ceder，Comput。母校 科学 68，314（2013）。

[2] R. Wu，AJ Freeman，《应用物理学杂志》 79，6209–6212（1996）。

[3] G. Kresse，J。Furthmüller，物理学。修订版B 54（1996）11169。

[4] S. Zhang和R. Zhang，计算机。物理 公社 220，403（2017）。