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 IrCl3 (Materials Project id mp-27666)

         7       10       10        0        5        0  
        10       80       28        0        3        0  
        10       28       79        0        2        0  
         0        0        0       23        0       -0  
         5        3        2        0        2        0  
         0        0        0       -0        0        3  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 29.111 GPaEV = 35.003 GPaGV = 13.467 GPaνV = 0.2996
ReussKR = -7.8579 GPaER = -29.674 GPaGR = -17.042 GPaνR = -0.12939
HillKH = 10.627 GPaEH = -5.682 GPaGH = -1.7878 GPaνH = 0.58912

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-1.3104 GPa 3 GPa 8.1856 GPa 23 GPa 51.505 GPa 109.62 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.