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 Hf2Tl (Materials Project id mp-1009238)

       106      145      129        0        0        0  
       145      106      129        0        0        0  
       129      129      139        0        0        0  
         0        0        0       94        0        0  
         0        0        0        0       94        0  
         0        0        0        0        0       69  

Average properties

Averaging schemeBulk modulusYoung's modulusShear modulusPoisson's ratio
VoigtKV = 128.56 GPaEV = 127.9 GPaGV = 47.933 GPaνV = 0.33418
ReussKR = 123.62 GPaER = 31.384 GPaGR = 10.765 GPaνR = 0.45769
HillKH = 126.09 GPaEH = 81.708 GPaGH = 29.349 GPaνH = 0.39199

Eigenvalues of the stiffness matrix

λ1 λ2 λ3 λ4 λ5 λ6
-39 GPa 4.165 GPa 69 GPa 94 GPa 94 GPa 385.84 GPa
Stiffness matrix is not definite positive, crystal is mechanically unstable
No further analysis will be performed.