[Pw_forum] how to perform a constraint calculation?

[Giuseppe Mattioli]

Dear Yu Hailin
Please remember always to sign your posts also with your scientific  
affiliation.
Look for the cell_dofree variable in the pw.x manual. A vc-relax  
calculation with cell_dofree='z' should accomplish the task.
HTH
Giuseppe

Giuseppe Mattioli
ISM-CNR
Italy

Quoting 于海林 <yuhailin_79 at 126.com>:

> Dear all
> I want to perform a constraint calculation for hexagonal GaN. The a  
> and b lattice constants are constrainted, and the c lattice constant  
> , cell volume and atomic accordinate are relaxed.
> But I don't know how to set the [CONSTRAINTS] card. I wish to get  
> your help. Thanks in advance!
>
>
> Best Regards!
> Yu Hailin


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