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Dear All,

<p>I am a new user of  the PWSCF code and  I succeed  with

calculations for

<br>cubic

<br>systems.  But,  doing a calculation for an orthorhombic system,

with the

<br>following

<br>reciprocal axes as the ouput file prints out:

<p>     reciprocal axes: (cart. coord. in units 2 pi/a_0)

<br>              

b(1) = (  1.0000 -1.4625  0.0000 )

<br>              

b(2) = (  1.0000  1.4625  0.0000 )

<br>              

b(3) = (  0.0000  0.0000  1.0740 )  .

<p>I got some troubles.  Actually, I used more precision in the vectors

of the

<br>reciprocal

<br>lattice in order to generate the q-point grid (1.462525295 and

<br>1.073961926).  Some of

<br>the q-points are:

<p>0.0000000000  0.0000000000  0.2684904815

<br>0.0000000000  0.0000000000  1.0739619260

<br>0.5000000000  0.3656313238  0.2684904815

<br>0.2500000000 -0.3656313238  0.2684904815

<br>0.2500000000 -0.3656313238  0.5369809630

<br>0.2500000000 -0.7312626475  0.5369809630

<br>0.5000000000 -0.3656313238  0.2684904815

<br>1.0000000000 -0.3656313238  0.2684904815

<br>etc., etc.,

As you can  see, they are commensurable with the reciprocal lattice.

The dynamical matrix calculation for all these q-points has been done.

But,

<br>when I run

<br>the q2r.x  program to  get the interatomic foces constants

in real space I

<br>got the

<br>following:

<p> q=   0.00000000  0.00000000  0.00000000

<br>  reading dyn.mat. from file ti.dyn_0.00_0.00_0.26

<br>  nqs=   2

<br> q=   0.00000000  0.00000000  0.26849048

<br>   1   1   1

<p> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

<br>     from init : error #        

1

<br>      nc already filled

<br> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

<p>or for example

<p> q=   0.00000000  0.00000000  0.00000000

<br>  reading dyn.mat. from file ti.dyn_0.05_0.36_0.26

<br>  nqs=   4

<br> q=   0.50000000  0.36563132  0.26849048

<br>   1   1   1

<p> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

<br>     from init : error #        

1

<br>      nc already filled

<br> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Has someone the same kind of error before?

How could I solve this?

Is it related with the q-point grid?

Any good sugestion that you can give me it is very welcome.

<p>With best,

<p>Jorge Osorio

<br> 

<br> 

<pre>-- 

Jorge Mario Osorio Guillen   |Telephone: (46-018)-471 35 67

Condensed Matter Theory Group|Fax: (46-018)-471 35 24

Department of Physics        |e-mail: Jorge.Osorio@fysik.uu.se

Uppsala University           |www.fysik4.fysik.uu.se

Box 530                      |

SE-751 21 Uppsala-Sweden     |</pre>

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