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 Ca3Cu2(ClO2)2 (Materials Project id mp-23095)

       181       80       25        0        0        0  
        80      181       25        0        0        0  
        25       25        4        0        0        0  
         0        0        0       28        0        0  
         0        0        0        0       28        0  
         0        0        0        0        0       71  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 69.556 GPaEV = 103.08 GPaGV = 41.133 GPaνV = 0.253
ReussKR = -1.2189 GPaER = -4.5622 GPaGR = -2.6034 GPaνR = -0.1238
HillKH = 34.168 GPaEH = 48.651 GPaGH = 19.265 GPaνH = 0.26269

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-0.77509 GPa 28 GPa 28 GPa 71 GPa 101 GPa 265.78 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.