MechElastic: A Python Library for Analysis of Mechanical and Elastic Properties of Bulk and 2D Materials

TL;DR

MechElastic is a Python library that analyzes mechanical and elastic properties of bulk and 2D materials from DFT outputs, enabling high-throughput material characterization and visualization.

Contribution

It introduces a versatile Python package that processes DFT elastic data, detects crystal symmetry, tests stability, and visualizes elastic properties, streamlining high-throughput material analysis.

Findings

Supports multiple DFT codes like VASP, ABINIT, Quantum Espresso

Calculates a wide range of elastic and mechanical properties

Provides visualization tools for elastic property variation

Abstract

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 parameter, and Lame's coefficients, can be estimated using this program. Another existing feature of this program is to employ the ELATE package [J. Phys.: Condens. Matter 28, 275201 (2016)] 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.