[Pw_forum] real space mesh

[Paolo Giannozzi]

On Thursday 02 February 2006 10:21, Stefano Baroni wrote:

> In real space, the (i,j,k) point of the mesh is
>
> (i-1)*tau_1 + (j-1)*tau_2 + (k-1)* tau_3
>
> where the tau's are the basis vectors of the Bravais lattice.

actually it is 

r(i,j,k) = (i-1)*tau_1/nr1 + (j-1)*tau_2/nr2 + (k-1)* tau_3/nr3

where nr1, nr2, nr3 are the dimensions of the FFT in the three crystal 
axis. Note that r(nr1,j,k) is equivalent to r(1,j,k) and so on because of
periodic boundary conditions.

P.
-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
Piazza dei Cavalieri 7      I-56126 Pisa, Italy