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 ZrCl3 (Materials Project id mp-569391)

         8       51       -0        0        4        0  
        51        8       -0        0       -4        0  
        -0       -0        3        0        0        0  
         0        0        0       -0        0       -4  
         4       -4        0        0       -0        0  
         0        0        0       -4        0      -21

Average properties

Averaging scheme	Bulk modulus	Young's modulus	Shear modulus	Poisson's ratio
Voigt	K_V = 13.444 GPa	E_V = -22.539 GPa	G_V = -6.3333 GPa	ν_V = 0.77941
Reuss	K_R = 2.7231 GPa	E_R = 4.0279 GPa	G_R = 1.6067 GPa	ν_R = 0.25347
Hill	K_H = 8.0838 GPa	E_H = -7.8555 GPa	G_H = -2.3633 GPa	ν_H = 0.66196

Eigenvalues of the stiffness matrix

λ₁	λ₂	λ₃	λ₄	λ₅	λ₆
-43.732 GPa	-21.736 GPa	0.73173 GPa	0.7361 GPa	3 GPa	59 GPa

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

Code version: 2020.07.26 (running on Python 3.7.2)