This is possibly a sign that the RMM-DIIS algorithm is failing in your electronic minimization.  If you change ALGO = Fast to ALGO = Normal, the RMM is not used, which may solve the problem.

Also, a good resource for solving common errors in VASP is to look at the custodian package (see first link below).  If you implement it in your workflow, it will handle many common VASP errors automatically.  If you just want to know how it attempts to fix a specific error, take a look at the VASP error handler module code (see second link below).  By searching for the specific error message in the code, you can see what custodian does to try to avoid it.

Another option would be to run your calculations with aflow, a program from the Curtarolo group (see third link below).  It also attempts to handle common VASP errors automatically.  You can also look through the aflow documentation to see how it attempts to correct for common errors.

http://pythonhosted.org/custodian/

http://pythonhosted.org/custodian/_modules/custodian/vasp/handlers.html

http://materials.duke.edu/aflow.html

There are possible different reasons for this result: 1) bad condition number of input matrix; 2) divergent calculation process; 3)..

At which iteration step happened an interruption of computing?

This is possibly a sign that the RMM-DIIS algorithm is failing in your electronic minimization.  If you change ALGO = Fast to ALGO = Normal, the RMM is not used, which may solve the problem.

Also, a good resource for solving common errors in VASP is to look at the custodian package (see first link below).  If you implement it in your workflow, it will handle many common VASP errors automatically.  If you just want to know how it attempts to fix a specific error, take a look at the VASP error handler module code (see second link below).  By searching for the specific error message in the code, you can see what custodian does to try to avoid it.

Another option would be to run your calculations with aflow, a program from the Curtarolo group (see third link below).  It also attempts to handle common VASP errors automatically.  You can also look through the aflow documentation to see how it attempts to correct for common errors.

http://pythonhosted.org/custodian/

http://pythonhosted.org/custodian/_modules/custodian/vasp/handlers.html

http://materials.duke.edu/aflow.html

Dear Professor Stepan Syrotyuk,

Thank you so much for your answer and suggestion. 

The error message happens at Iteration 17(9). Any suggestion will be highly appreciated.

Best,

Liaoyuan

Dear Dr. Michael T Garvey,

Thank you so much for your explanation, suggestion, and useful links. I will study it and discuss with you late. Thanks again.

Appreciatively,

Liaoyuan

Why iterative process becomes divergent? This is the main question. I this case I try to control the matrix system of equations at each iteration step. To do this, I type sum of modules squares diagonal and non-diagonal elements separately. If the ratio of these amounts increases, the process diverges. Hence, the reason for the differences in the matrix.  

Hi,

I have same error in my calculations. Any solution has been found? or any suggestions?

Thanks

I got same error thus i used ALGO = Normal instead of ALGO = Fast as suggest by Michael T Garvey and it is solved now.

Thank You.

The error "LAPACK: Routine ZPOTRF failed! 1 1 1" can be solved by slightly increasing the value of POTIM. I observed that changing ALGO from Fast to Normal, and increasing the NBANDS value do not help in this case.

Maitrayee Ghosh Hi Maitrayee, I got this "LAPACK: Routine ZPOTRF failed! 1 1 1" error after the first relaxation step but changing the POTIM tag is not helping me to get rid of it. In wonder if you have similar experiences?

Dongsheng Wen Did you try reducing POTIM? Sometimes, decreasing POTIM also helps. For me, this error got fixed by tweaking POTIM.

Maitrayee Ghosh I did that as well. VASP forum suggested us to check POSCAR but I don't see what problem could happen to my POSCAR.

Dongsheng Wen Possibly, the ions in POSCAR might be overlapping and the 'big' POTIM might not be able to catch that.

Maitrayee Ghosh The funny thing is that my POSCAR file is correct. I attach it here. I basically tried POTIM from 0.1 to 0.001 but the error didn't go away.

Could you send the other input files? I can give a try. Dongsheng Wen

Maitrayee Ghosh That would be awesome if you could help me take a look!