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 CaC2 (Materials Project id mp-2482)

        95       26       19        0        0        0  
        26       95       19        0        0        0  
        19       19      224        0        0        0  
         0        0        0       -1        0        0  
         0        0        0        0       -1        0  
         0        0        0        0        0       39  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 60.222 GPaEV = 78.796 GPaGV = 30.733 GPaνV = 0.28193
ReussKR = 53.513 GPaER = -7.8925 GPaGR = -2.5884 GPaνR = 0.52458
HillKH = 56.868 GPaEH = 39 GPaGH = 14.072 GPaνH = 0.3857

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-1 GPa -1 GPa 39 GPa 69 GPa 114.41 GPa 230.59 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.