Dear Stefano,<br>
Thank you very much for your previous email. <br>
However, I am now calculating esp_0 of
bulk LaAlO3. For a polar material with large dielectric constant, I
expect esp_0 is much larger than esp_infty. But since all the forces on
the atoms are zero, the code does not know how to move the atoms
when I relax them.<br>
By the way, how to calculate esp_0 in
principle? Shall I relax the structure while turning on the electric
field?<br>
Sorry to bother you again.<br>
<br>
Hanghui<br>
Department of Physics,<br>
Yale University<br>