[Pw_forum] Questions about plotting

[glevita at units.it]

Dear PW users,
My name is Giacomo Levita, and I have a couple of questions, both  
quite naive. I tried to search in the Forum archive to get some hints,  
but I have to rely on your advice.

I am trying to evaluate the LDOS (at different energies) of an  
isolated planar molecule (PVBA), for which I got a relaxed structure I  
am satisfied with. I am interested in calculating the LDOS only in  
certain points of the molecule.
The first question is therefore: is it possible to have a numerical  
value of the LDOS around points I can choose in my supercell? I mean:  
is there any postprocessing tool in which by providing x,y,z,R and E,  
the LDOS within a sphere of radius R centred around a xyz point for  
the given energy E is obtained?

Second: being unable to extract easily manageable numerical values out  
of the XSF file obtained for some |Psi^2|, I decided to create a  
series of one dimensional plots, related to vectors parallel to the  
molecular axis, out of which I'll extract some preliminary info. To  
test this tool, I tried to plot the charge density (as a test) on a  
certain direction. This was my input file:

  &inputpp
     prefix  = 'PVBA'
     outdir = './'
     filplot = 'projlin'
     plot_num= 0
  /
  &plot
     nfile = 1
     filepp(1) = 'projlin'
     weight(1) = 1.0
     iflag = 1
     output_format = 3
     fileout = 'projlin.ldos.xsf'
     e1(1)= 0.0, e1(2)= 0.0, e1(3)= 1.0,
     x0(1)= 0.0, x0(2)= 0.1, x0(3)= 0.0,
     nx= 100
  /

There must be something wrong with that, as the file 'projlin' is  
correctly generated, but the related XSF file is not. Actually, the  
job keeps running without any advance in writing the XSF file (it  
doesn't crash). These are the last lines of the output file (I  
submitted as an MPI parallel job on 64 processors):
...
  61      5    292  64124    3     98  12354   24   1548
  62      5    292  64124    3     98  12354   24   1548
  63      5    292  64120    3     98  12354   24   1544
  64      5    292  64116    3     98  12346   24   1544
   0    360  186014103263  192   6205 789671 1555  98693


      nbndx  =    50  nbnd   =    50  natomwfc =    79  npwx   =     774
      nelec  =  84.00  nkb   =   147  ngl    =    8205

      negative rho (up, down):  0.315E-01 0.000E+00

      Calling punch_plot, plot_num =   0
      Writing data to file  projlin
      Reading header from file  projlin
      Reading data from file  projlin

      Writing data to be plotted to file projlin.ldos.xsf


The file just ends like this, and nothing is written in the .XSF file.  
I am very suspicious about that line of the output starting with 0, at  
the end of the grid description. Needless to say, the same result is  
obtained when I change nx or e0 in my input file. Does anyone have any  
suggestion about this problem?

I thank you very much for your help; sorry for this wordy message.
  Giacomo


----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.