ELATE: Elastic tensor analysis

Welcome to ELATE, the online tool for analysis of elastic tensors, developed by Romain Gaillac and Fran├žois-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 WN (Materials Project id mp-1001828)

       260      290      290        0        0        0  
       290      260      290        0        0        0  
       290      290      260        0        0        0  
         0        0        0     -241        0        0  
         0        0        0        0     -241        0  
         0        0        0        0        0     -241  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 280 GPaEV = -550.5 GPaGV = -150.6 GPaνV = 0.82768
ReussKR = 280 GPaER = -107.27 GPaGR = -34.298 GPaνR = 0.56385
HillKH = 280 GPaEH = -311.65 GPaGH = -92.449 GPaνH = 0.6855

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-241 GPa -241 GPa -241 GPa -30 GPa -30 GPa 840 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.