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 TlPt (Materials Project id mp-11553)

       118      109       44        0        0        0  
       109      118       44        0        0        0  
        44       44      -31        0        0        0  
         0        0        0       16        0        0  
         0        0        0        0       16        0  
         0        0        0        0        0        5  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 66.556 GPaEV = 22.89 GPaGV = 7.9333 GPaνV = 0.44268
ReussKR = 991.73 GPaER = 29.28 GPaGR = 9.7921 GPaνR = 0.49508
HillKH = 529.14 GPaEH = 26.441 GPaGH = 8.8627 GPaνH = 0.49167

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-45.224 GPa 5 GPa 9 GPa 16 GPa 16 GPa 241.22 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.