hi, suppose you know the 2/3 structures between which the phase transition occurs, then calculate E-vol for all the 2/3 structures...keep vol range same...or vol/unit-formula-unit same. the curves will cross. draw a common tangent...slope gives the pressure of transition. for 3 structures you will have to draw tangents between pairs for which transition is expected. s.auluck
> Thanks Sushil, > I know that we can do it from E-V, but I want to see the transition > volume, a jump in PV curves. I would like to do calculations on Pressure > vs volume. because we know at transition there is jump in the volume, > there are many articles in the literature which do PV calculations. > Any Idea? > > > --- On Sat, 9/3/11, Sushil Auluck <[email protected]> wrote: > > > From: Sushil Auluck <[email protected]> > Subject: Re: [SIESTA-L] Pressure_Volume_Calculations > To: [email protected] > Date: Saturday, September 3, 2011, 9:42 AM > > > hi, > calculate Energy vs Volume. then using P= -dE/dV gives you pressure P. > s.auluck > >> Hi, >> How to perform explicitly Pressure vs Volume or Pressure vs Energy >> calculations to see the transition pressure. I know one can use prof. >> Apostnik's tool to find the transition pressure from E-V calculations, >> but >> I want P-V or P-E calculations with SIESTA. How to do this? >> Mic. >> > > > ....................................................................... > Prof. Sushil Auluck Phone:+91-512-6797092/6148 > Department of Physics +91-512-6798177(Home) > Indian Institute of Technology Cell :+91-9305548667 > Kanpur 208016 (UP) Fax :+91-512-6790914 > India E-mail:[email protected] > ...............................................:[email protected] > http://www.iitk.ac.in/phy/People/phy_facvis.html > http://www.iitk.ac.in/phy/New01/profile_SA.html > ....................................................................... > ~ > ....................................................................... Prof. Sushil Auluck Phone:+91-512-6797092/6148 Department of Physics +91-512-6798177(Home) Indian Institute of Technology Cell :+91-9305548667 Kanpur 208016 (UP) Fax :+91-512-6790914 India E-mail:[email protected] ...............................................:[email protected] http://www.iitk.ac.in/phy/People/phy_facvis.html http://www.iitk.ac.in/phy/New01/profile_SA.html ....................................................................... ~
