The MechElastic Python package evaluates the mechanical and elastic properties of bulk and 2D materials using the elastic coefficient matrix ($C_{ij}$) obtained from any ab-initio density-functional theory (DFT) code. The current version of this package reads the output of VASP, ABINIT, and Quantum Espresso codes (but it can be easily generalized to any other DFT code) and performs the appropriate post-processing of elastic constants as per the requirement of the user. This program can also detect the input structure's crystal symmetry and test the mechanical stability of all crystal classes using the Born-Huang criteria. Various useful material-specific properties such as elastic moduli, longitudinal and transverse elastic wave velocities, Debye temperature, elastic anisotropy, 2D layer modulus, hardness, Pugh's ratio, Cauchy's pressure, Kleinman's parameter, and Lame's coefficients, can be estimated using this program. Another existing feature of this program is to employ the ELATE package (2016) [29] and plot the spatial variation of several elastic properties such as Poisson's ratio, linear compressibility, shear modulus, and Young's modulus in three dimensions. Further, the MechElastic package can plot the equation of state (EOS) curves for energy and pressure for a variety of EOS models such as Murnaghan, Birch, Birch-Murnaghan, and Vinet, by reading the inputted energy/pressure versus volume data obtained via numerical calculations or experiments. This package is particularly useful for the high-throughput analysis of elastic and mechanical properties of materials.

Program summary

Program Title: MechElastic

CPC Library link to program files: https://doi.org/10.17632/y9zc7zybrm.1

Developer's repository link: https://github.com/romerogroup/MechElastic

Licensing provisions: GPLv3

Programming language: Python

Nature of problem: To automatize and simplify the analysis of elastic and mechanical properties for bulk and 2D materials, especially for high-throughput DFT calculations.

Solution method: This Python program addresses the above problem by parsing the elastic coefficient matrix obtained from the first-principles DFT calculations, does the appropriate post-processing to evaluate the elastic properties, and performs the mechanical stability tests for all crystal classes using the generalized Born-Huang criteria. It can also be used to carry out the equation of state analysis to study the structural phase transitions.

Additional comments: MechElastic can be downloaded using the below link: https://github.com/romerogroup/MechElastic

Installation (via PyPI): pip install mechelastic, or pip3 install mechelastic

中文翻译：

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MechElastic：一个 Python 库，用于分析散装和 2D 材料的机械和弹性特性

所述MechElastic Python包评估散装的机械性能和弹性和2D的材料使用弹性系数矩阵（$C_{\mathrm{一世}j}$) 从任何ab-initio密度泛函理论 (DFT) 代码中获得。这个包的当前版本读取 VASP、ABINIT 和 Quantum Espresso 代码的输出（但它可以很容易地推广到任何其他 DFT 代码），并根据用户的要求对弹性常数进行适当的后处理。该程序还可以检测输入结构的晶体对称性，并使用 Born-Huang 标准测试所有晶体类别的机械稳定性。各种有用的材料特定属性，例如弹性模量、纵向和横向弹性波速度、德拜温度、弹性各向异性、2D 层模量、硬度、Pugh 比、Cauchy 压力、Kleinman 参数和 Lame 系数，可以使用该程序进行估计。该程序的另一个现有功能是采用 ELATE 包 (2016) [29]并在三个维度上绘制泊松比、线性压缩率、剪切模量和杨氏模量等几种弹性特性的空间变化。此外， MechElastic包可以通过读取所输入的能量/压力绘制为能量和压力状态（EOS）曲线的方程，适用于各种EOS模型如Murnaghan状态，桦木，桦木-Murnaghan状态，和Vinet是，的相对于获得的体数据经由数值计算或实验。该软件包对于材料的弹性和机械性能的高通量分析特别有用。

程序概要

程序名称： MechElastic

CPC 库程序文件链接： https : //doi.org/10.17632/y9zc7zybrm.1

开发者仓库链接： https : //github.com/romerogroup/MechElastic

许可条款： GPLv3

编程语言： Python

问题性质：自动化和简化块状和二维材料的弹性和机械性能分析，尤其是高通量 DFT 计算。

解决方法：这个Python程序通过解析第一性原理DFT计算得到的弹性系数矩阵来解决上述问题，做适当的后处理来评估弹性性能，并使用广义的晶体类对所有晶体类进行机械稳定性测试出生黄标准。它还可用于进行状态方程分析以研究结构相变。

附加说明： MechElastic可以使用以下链接下载：https://github.com/romerogroup/MechElastic

安装（通过PyPI）：pip install mechelastic 或 pip3 install mechelastic