ELATE: Elastic tensor analysis

Welcome to ELATE, the online tool for analysis of elastic tensors, developed by Romain Gaillac and François-Xavier Coudert at CNRS / Chimie ParisTech.
If you use the software in published results (paper, conference, etc.), please cite the corresponding paper (J. Phys. Condens. Matter, 2016, 28, 275201) and give the website URL.

ELATE is open source software. Any queries or comments are welcome at

Summary of the properties

Input: stiffness matrix (coefficients in GPa) of TaS2 (Materials Project id mp-10014)

       169       55      -11       -0        0        0  
        55      169      -11        0        0        0  
       -11      -11       -8        0        0        0  
        -0        0        0        4        0        0  
         0        0        0        0        4       -0  
         0        0        0        0       -0       57

Average properties

Averaging scheme	Bulk modulus	Young's modulus	Shear modulus	Poisson's ratio
Voigt	K_V = 44 GPa	E_V = 78.816 GPa	G_V = 32.8 GPa	ν_V = 0.20146
Reuss	K_R = -8.0714 GPa	E_R = 75.451 GPa	G_R = 12.337 GPa	ν_R = 2.058
Hill	K_H = 17.964 GPa	E_H = 47.721 GPa	G_H = 22.568 GPa	ν_H = 0.057259

Eigenvalues of the stiffness matrix

λ₁	λ₂	λ₃	λ₄	λ₅	λ₆
-9.0385 GPa	4 GPa	4 GPa	57 GPa	114 GPa	225.04 GPa

Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.

Code version: 2022.06.14 (running on Python 3.7.2)