Hi Janakiraman, 



 In transiesta the z-direction is that of charge transport. In other words it 
is non-periodic. Therefore, when transiesta runs it will override the user's 
choice of k-points in this direction. If you pick k-points along the x and y 
directions transiesta should keep them though. The number of k-points you get 
might be smaller than the number you assign on the Kgrid_Mohorst pack lines 
because of symmetry reasons. 



 Best regards, 

-Salvador. 



----- Original Message -----
From: "janakiraman balachandran" <[email protected]> 
To: [email protected] 
Sent: Friday, April 22, 2011 4:28:51 PM 
Subject: [SIESTA-L] questions regarding Kgrid_Monhorst in Transiesta 

Hi 

I have been trying to understand the Kgrid_Monhorst pack. I ran a simple 111 
calculation of Au atoms with the following Monhorst pack values 

%block kgrid_Monkhorst_Pack 
  1   0   0    0.0 
  0   1   0    0.0 
  0   0   12   0.0 
%endblock kgrid_Monkhorst_Pack 


When i perform a simple siesta calculation ( using siesta 1.3p ), i get as 
expected 7 K points as follows 

  1    0.000000    0.000000    0.000000       0.083333 
     2    0.000000    0.000000    0.038179       0.166667 
     3    0.000000    0.000000    0.076358       0.166667 
     4    0.000000    0.000000    0.114537       0.166667 
     5    0.000000    0.000000    0.152716       0.166667 
     6    0.000000    0.000000    0.190895       0.166667 
     7    0.000000    0.000000    0.229074       0.083333 

However when i run the same calculation in transiesta rc2 with the identical 
fdf file, i get only the Gamma point in the .KP file. I dont understand why I 
could not systematically increase the kpoints in transiesta. Am I making some 
mistake? Is there a new way to systematically increase k point sampling in 
transiesta 


 I have attached the fdf and the corresponding psf file along with the email. 
Any help regarding the same would be of great help. 

Regards 
Ram 




-- 
Salvador Barraza-Lopez 
Postdoctoral Fellow 
School of Physics 
The Georgia Institute of Technology 

Office N205 
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