[Pw_forum] Finding the most stable structure

[庞瑞(PANG Rui)]

Dear reza
I think the proper way of doing this job is by some optimization algrithoms such as genetic algrithom and particle swarm algrithom. You can write a small srcript to implement these algrithoms and call pw.x to calculate the energy. As alternation, there are some open source software interfaced with pw.x can do this job such as CALYPSO. If the structure is not the major property you concern, you can use a MD process and reduce the temperature step by step.
Good luck
PangRui




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庞瑞(PANG Rui)



South University of Science and Technology of China/Department of Physics

No.1088,Xueyuan Road, Shenzhen,Guangdong







 
 
 
------------------ Original ------------------
From:  "reza vatan"<rezavatan64 at gmail.com>;
Date:  Mon, Sep 28, 2015 03:54 AM
To:  "PWSCF Forum"<pw_forum at pwscf.org>; 

Subject:  [Pw_forum] Finding the most stable structure

 
Dear all,


I have a supercell containing 64 Si atoms with amorphous structure and I want to add one Hydrogen atom to one of Si atoms with the condition that the most stable possible structure comes out. I randomly add the Hydrogen to one of Si atoms and then I run "relax" calculations, but I get different final energy when I repeat my random process for adding the Hydrogen. Should I try "md" calculations to get the same structure with the most stability out of my different initial structures? If yes under which conditions (options)?


Any suggestion would be highly appreciated.


Best,

Reza     

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Reza Vatan Meidanshahi

Electrical Engineering Department

Arizona State University
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