[Pw_forum] K_POINTS, tpiba or crystal

[Axel Kohlmeyer]

On Mon, 29 Dec 2008, Paul M. Grant wrote:


hi paul,

PG> When specifying a user generated mesh for an nscf run, should tpiba (the
PG> default) or crystal coordinates be designated on the  K_POINTS card?

most likely tpiba.

PG> Frankly, I don't understand what "crystal" means wrt to reciprocal space
PG> (ATOMIC_POSITIONS, yes), and it does seem to make a small difference

in my understanding, crystal would be multiples of the 
reciprocal lattice vectors, i.e. the "b"-matrix printed
out at the beginning of a job.

cheers,
   axel.

PG> depending on the application (e.g. Fermi surface generation).


PG> 
PG> A Merry Winter Solstice Break to All.
PG> 
PG> Paul M. Grant, PhD
PG> Principal, W2AGZ Technologies
PG> Visiting Scholar, Applied Physics, Stanford (2005-2008)
PG> EPRI Science Fellow (Retired)
PG> IBM Research Staff Member Emeritus
PG> w2agz at pacbell.net
PG> http://www.w2agz.com <http://www.w2agz.com/> 
PG>  
PG>  
PG> 
PG> 
PG> 

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