no i have calculated correctly because the convergence is good with higher k points second is that i have tested zns,wc,NiAs phase none of them have less enthalpy at 130 gpa other thing is that it is stable at above 250 gpa
On Wed, Aug 24, 2011 at 7:38 PM, Mike Mehl <Michael.Mehl at nrl.navy.mil>wrote: > If the B1 structure is unstable with respect to the B2 structure above > 130 GPa, but the B2 structure is dynamically unstable at and above 130 > GPa, there are two possible conclusions: > > 1) The phonons for the B2 structure were not calculated accurately, or > > 2) There is a competing structure that is lower in enthalpy than B1 or > B2 at 130 GPa > > Without more information, no one can judge which conclusion is correct, > suggest remedies for 1), or possible structure for 2). > > > On 08/23/2011 02:40 PM, bhabya sahoo wrote: > > sir > > i am calculating the phase transition of some carbides > > the transition from B1 to B2 transition occures at 130 gpa by enthalpy > > compparison > > but i am able to find phonon instability at 130 gpa for B1 structure > > but at the same time i am not able to find the dyanamic stability of B2 > > phase > > but it occures high pressure (more than130 gpa ) > > is there any explanation for this ? > > > > is there any relation of thermodyanamical unstability > > and dyanamical unstability simultaneously? > > > > > > answers are highly appriceted with some reson > > > > > > > > > > > > > > > > > > Bd sahoo > > reserch scholar > > barc mumbai > > > > > > > > _______________________________________________ > > Pw_forum mailing list > > Pw_forum at pwscf.org > > http://www.democritos.it/mailman/listinfo/pw_forum > > > -- > Michael J. Mehl > Head, Center for Computational Materials Science > Naval Research Laboratory Code 6390 > Washington DC > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110824/9903e9cd/attachment.htm