[Pw_forum] polarizability perpendicular to metal surface

[Andrea Benassi]

Dear Garold,
enclosed in the lates version of Espresso you can find a post
processing named epsilon.x and its manual eps_man.tex in the Doc
folder. With epsilon.x you can calculate dielectric tensor within the
LDA approximation, eels spectra and London transform of the dielectric
tensor (epsilon on imm axe). It should be extremely easy to modify the
code in order to give the polarizability instead of the dielectric
function.
The code works as an ordinary pw post processing, it works both for
metal and semiconductors and it supports pool paralelization and
collinear spin calculation.
I used the same code many times to calculate dielectric functions in
order to estimate the Casimir force between plates.
I recommend you to use the CVS version of epsilon.x
Good luck
-- 
Andrea Benassi
National Research Center S3, CNR-INFM  ( http://www.s3.infm.it )
Dipartimento di Fisica, Universita' di Modena e Reggio Emilia
Via Campi 213/A I-41100 Modena, Italy
Tel:     +39 059 2055314
Fax:     +39 059 374794
E-mail:  benassi.andrea at unimore.it
URL:     http://www.nanoscience.unimo.it