[Wien] [Wien2k Users] Lattice Stability using Structure Optimization

[Ghosh SUDDHASATTWA]

Dear Stefaan, 
Probably you are right. But then how to tackle with the point you raised
(point no.2)
One thing would be to vary c/a with constant volume (option 2), but then I
do not have a priori information on the optimized parameters. 
Suddhasattwa Ghosh 

-----Original Message-----
From: wien-bounces at zeus.theochem.tuwien.ac.at
[mailto:wien-bounces at zeus.theochem.tuwien.ac.at] On Behalf Of Stefaan
Cottenier
Sent: Monday, March 08, 2010 7:53 PM
To: A Mailing list for WIEN2k users
Subject: Re: [Wien] [Wien2k Users] Lattice Stability using
StructureOptimization


1) I hope you know what you are plotting if you make a 2D (a,c) scan and 
then "chose energy vs volume in plot".

2) Think about this: a section of a parabola far away from its minimum 
might look like a straight line.

Stefaan


> Coming back to the problem we discussed regarding lattice stability a 
> few days back, I have done a few things but am not able to proceed
further.
> 
> I imagine Pu in a Zr lattice (hcp, space group 194)
> 
> There is only one equivalent position (0.3333333 0.666667 0.25)
> 
> I replaced Zr atom with the Pu atom.
> 
> My approach was the following
> 
>    1. Calculate ENE without spin orbit and with spin orbit
>    2. Structure optimization (Option 5)
> 
>  
> 
> The ENE without spin orbit was -118767.962 Ry and with spin orbit was 
> -118769.097 Ry.
> 
> I chose Option 5 for the structure optimization and it created 16 
> different struct files.
> 
> Optimize.job was run and it did not give any errors. (Removed # from x 
> dstart only)
> 
> When I chose energy vs volume in plot; it gave a linear variation and 
> not like what is given in the UG guide for TiC.
> 
> Can you please tell me if I have done any mistake?
> 
>  
> 
> Suddhasattwa Ghosh
> 
>  
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien


-- 
Stefaan Cottenier
Center for Molecular Modeling (CMM)
Ghent University
Technologiepark 903 (2nd floor)
BE-9052 Zwijnaarde
Belgium

http://molmod.Ugent.be
email: Stefaan . Cottenier /at/ UGent . be
_______________________________________________
Wien mailing list
Wien at zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien