ABINIT Discussion Forums

Dear colleagues,

I am having troubles using anaddb to obtain relaxed ion elastic constants. Running anaddb ends with a note:

** On entry to ZHPEV parameter number 7 had an illegal value

Could anyone help me and explain what this error means and give me suggestions how to continue my calcs?
I read that it is connected with zhpev.f90 routine which diagonalizes matrices, but nothing more.
My rf elastic clalc ends without warnings and I merged ddbs from datasets 1 (gs) and 3 (rf) before running anaddb.

I am interested in metallic Ce, and using abinit 5.8.4 on a Linux cluster.

Thank you all in advance!

Yours,
Igor Lukacevic

PS. Input file is attached

Hello Igor,

argument 7 is the dimension of the eigenvalue matrix. I see that

src/77_ddb/piezo9.F90

has a call with arg7 = 3*natom-3 = 0 in your case. I believe the piezo constants have no meaning if you only have 1 atom (no internal degrees of freedom to relax). There should be a check in the code to avoid this, but basically it probably means there is no "relaxed ion" you can define here.

ciao!

Matthieu

Dear Matthieu,

thank You for the explanation. That solves the issue. Actually, a part of this answer was given to me last week by Razvan, but I hadn't time to put it on the forum.

Cheers!

Igor L.

You can try the unit cell. With more than two atoms per cell, anddb works well!

regards

alejandro