[Pw_forum] charge density and pot file

[Paolo Giannozzi]

On Tuesday 11 October 2005 17:41, Lilia Boeri wrote:

> In particular, I have problems in locating which part of the code
> attaches an index "ig" to a particular plane wave: i.e. how is the 
> index i related to ix, iy,iz?

it depends on what ix, iy, iz are ... There are two different ways
of storing G-components. One is as list of components for 
wavevector g_i (i=1,ngm): g_i = ( G(1,i), G(2,i), G(3,i) ) * 2pi/a,
where variable G is contained in module gvect. The other way
is the "FFT grid" that is used to perform FFT. The latter is
related to the former by a set of indices NL: rho(g_i) = rho_fft(nl(i))
Unless you need to do something special, this should be more
or less all you need

Paolo

-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
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