[Pw_forum] How to control number of slabs in pwcond calculation？

[Manoj Srivastava]

Dear Hui Wang, 
 I dont think there is a straight forward way of doing this, at least not
that I know of. (Community members are most welcome to correct me on
this).changing the number of slabs along z direction is determined using
the unit cell length along z direction. Here is what I found upon some
grep. I tried to show here only when we have only one region present, lets
say left lead.
 from cond_out.f90
 do k=1, nrzl
       write(stdout,'(2x,i3,2x,3f7.4,3x,80i1)')                   &
         k,zl(k),zl(k+1),zl(k+1)-zl(k),(crosl(iorb,k),iorb=1,norbl)
 enddo
so if you wish to change the number of slabs along z direction, you need
to change nrzl and so on 
 from init_cond.f90
line 211 
 nrzl = nrzreg(1)
line 86
nrz1=0.0
do iz = 2, 5
     naux=(dwid(iz)+dz1*0.5d0)/dz1-nrz1
     nrzreg(iz-1) = naux
  ...
  .... 
 we have two options, dz1 and dwid(2)
line 44
 nrztot = nr3s
  if(nrztot/2*2.eq.nrztot) nrztot = nrztot+1
  zlen = at(3,3)
  dz1 = zlen/nrztot 
 zlen=z component of a_3 lattice vector. nr3s=
smooth fft dimension in z direction, so if you could change nr3s, you
might be able to change nrzl. 
 now, dwid(2)- line 80
 dwid(2) = bd2
line 60 
 if(flag.eq.'l') then
    bd2 = bdl
 from the input file description - 
bdl: right boundary of the left lead (left one is supposed to be at 0)

I dont know how one can change smooth fft dimesion in z direction. I
believe its done in SCF part not in PWCOND. 

Regards, 
Manoj

On Fri, 11 Sep 2009, xirainbow wrote:

> Dear all:      I find the following content at
> "/espresso-4.0.4/examples/example12/results/al.cond.out" file.
> *" nrz                      =           21*
> *.........*
> *    k slab    z(k)  z(k+1)     crossing(iorb=1,norb)*
> *    1   0.0000 0.0673 0.0673   111100000000*
> *.........*
> *   20   1.2793 1.3467 0.0673   000001111111*
> *   21   1.3467 1.4140 0.0673   000000001111  "*
> 
>      I want to know, at *.cond.in input file, how to control the number of
> slabs along z direction in left, right lead and scattering region,
> respectively.
>      By the way, what is the meaning of "crossing(iorb=1,norb)"?
> 
>      Thanks in advance ：）
> 
> 
> ____________________________________
> Hui Wang
> School of physics, Nankai University, Tianjin, China
>