Dear QE users, I have a question regarding,relaxaion of a scattering region for conductivity calculation in spin polarized case. I have individually relaxed and did scf calculation of electrodes and the molecule. When i try to relax the whole scattering region by fixing atoms except those of junction,the relax procedure takes too long and the force minimization fluctuates. Force decreases and increases. And at the end of the calculation i see a disturbed system,having distance between atoms of electrode much lesser than the distance i gave in input. I use au electrode.I got an au electrode input file from forum,which had au-au atomic distance 2.86. when i tried to make au electrode super cell from fcc structure,i got minima at 2.88A. When i use the electrode with 2.88A and 2.86A inter atomic distance,at the end of relax calculation, i get au-au distance between 2.68 to 2.80. Au-Au distance is not same for atoms. MY QUESTION IS, if i get such result at the end of a relax calculation which already took almost 1.5 days for 46 atoms system,what are the possible sources of my mistake, Do i need to check ''feasibility of my system" i am trying to make? How can we check feasibility of a system? or Do i need to check once more,the ground state of the molecule? and if i get the same result,what does that mean if it changes the geometry of the electrode in its presence? or I must be wrong in choosing 'right' parameters for relax calculation. or geometry i am giving in input.
Kindly give any suggestions or help in rectification. Thanking in advance, Yours faithfully Mudra R Dave Junior Research Fellow Theoretical Condensed Matter Physics Group, M S University of Baroda, Vadodara,Gujarat. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20131130/dc6c7ec2/attachment.html
