[Pw_forum] relax question

[Nicola Marzari]

xu yuehua wrote:
>  
> about why i use etot_conv_thr
> as well as  force_conv_thr= 1.d-6 Ry
> as usual,in vasp and castep software,about 1.d-4 ev is ok
> why it is so different between these DFT software ?
> i don not understand.
> need your help


The definition of what a convergence threshold is is probably
different.

Check into the source code of pwscf where etot_conv_thr is used,
and look at the documentation of the other codes.

It's like when you change cars - a British car on fifth gear will go
100 miles/h, an Italian car will go 180 km/h. They all do the same
thing.

				nicola

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