Dear APSI thank you for you suggestions to me.
I will try it ASAP. vega On Sun, Mar 1, 2009 at 5:08 PM, Ari Paavo Seitsonen <ari.p.seitsonen at iki.fi>wrote: > > Dear Vega, > > Just my guesses and suggestions: One could try mixing of the density, like > > &electrons > mixing_beta = 0.7 > / > > (or a value even smaller than 0.7, or some other parametres for the mixing) > since with a defect you might now have defect levels in the band gap, > leading to a more difficult a convergence. Eventually one could also switch > on the broadening of the occupation numbers, eventually switching it off for > the physical/production jobs, but just to check if the problem in > convergence comes due to this. > > And in the original paper the authors discuss spin-polarisation, one might > test also this (nspin = 2), with different initial magnetisations > [starting_magnetization(xx) = ...] for the atoms surrounding the defect. > > Greetings, > > apsi > > > On Sun, 1 Mar 2009, vega lew wrote: > > Dear all, >> >> I am planning to calculate the Oxygen vacancy properties of TiO2 surfaces. >> The calculation for the ideal surfaces are quite normal and the results >> are >> in line with the one that literature reported. But, when I tried to >> calculate the anatase 101 surface with an Oxygen vacancy (O2c was removed >> directly from the stoichiometric Anatase 101as described in J. Phys. Chem. >> C >> 2007, 111, 16397-16404, I encounter the problem of convergence for SCF >> cycle. I tried to add 20% more empty band to the system the problem still >> laid in. How could I overcome the problem? >> >> my input file was attached at the bottom of the mail >> >> thank you for reading. Any hints will be appreciated. >> >> vega >> >> > ... > > > >> &SYSTEM >> ibrav = 8, >> celldm(1) =19.3269, >> celldm(2) = 1.1094, >> celldm(3) = 1.7450, >> nat = 71, >> ntyp = 2, >> nosym = .true., >> ecutwfc = 30, >> ecutrho = 300, >> / >> >> &ELECTRONS >> >> / >> >> &IONS >> ion_dynamics = 'bfgs', >> / >> >> > -- > > -=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=- > Ari P Seitsonen / Ari.P.Seitsonen at iki.fi / > http://www.iki.fi/~apsi/<http://www.iki.fi/%7Eapsi/> > IMPMC, CNRS & Universit? Pierre et Marie Curie > Tel: +33-1-4427 7542, Fax: +33-1-4427 3785, GSM: +33-6-6736 3820 > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > -- ================================================================================== Vega Lew ( weijia liu) PH.D Candidate in Chemical Engineering State Key Laboratory of Materials-oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology, 210009, Nanjing, Jiangsu, China ****************************************************************************************************************** Email: vegalew at gmail.com Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing, Jiangsu, China ****************************************************************************************************************** -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20090301/30d4dd5c/attachment-0001.htm
