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 Ca2NbN3 (Materials Project id mp-1029832)

       194       68       44        0        0        0  
        68      161       32        0        0        0  
        44       32      107        0        0        0  
         0        0        0       -4        0        0  
         0        0        0        0      -35        0  
         0        0        0        0        0       49  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 83.333 GPaEV = 63.69 GPaGV = 23.2 GPaνV = 0.37262
ReussKR = 75.136 GPaER = -76.492 GPaGR = -22.906 GPaνR = 0.66967
HillKH = 79.235 GPaEH = 0.44051 GPaGH = 0.14693 GPaνH = 0.49907

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-35 GPa -4 GPa 49 GPa 88.223 GPa 107.72 GPa 266.06 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.