[Pw_forum] converge problem in calculating the vacancy on TiO2 surfaces
Eyvaz Isaev
eyvaz_isaev at yahoo.com
Sun Mar 1 14:17:08 CET 2009
Dear Vega,
It was explained many times in the case of surface calculations (you introduced a defect also) you should consider your system as metallic due to induced states (by dangling bonds or defects).
So, make your system metallic turning on occupations="smearing" and related keywords.
Of course, the use of mixing_mode='local-TF' and mixing_beta=0.1 is preferable in your calculations as your system is highly inhomogeneous.
Bests,
Eyvaz.
-------------------------------------------------------------------
Prof. Eyvaz Isaev,
Theoretical Physics Department, Moscow State Institute of Steel & Alloys, Russia,
Department of Physics, Chemistry, and Biology (IFM), Linkoping University, Sweden
Condensed Matter Theory Group, Uppsala University, Sweden
Eyvaz.Isaev at fysik.uu.se, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com
--- On Sun, 3/1/09, vega lew <quantumdft at gmail.com> wrote:
> From: vega lew <quantumdft at gmail.com>
> Subject: [Pw_forum] converge problem in calculating the vacancy on TiO2 surfaces
> To: "PWSCF Forum" <pw_forum at pwscf.org>
> Date: Sunday, March 1, 2009, 11:19 AM
> 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
>
>
>
> &CONTROL
>
> title = 'Anatase 101 1x3'
> ,
> calculation = 'relax'
> ,
> restart_mode = 'from_scratch'
> ,
> outdir = '/tmp/' ,
> wfcdir = '/tmp/'
> ,
> pseudo_dir =
> '/home/vega/espresso-4.0/pseudo/' ,
> prefix = 'Anatase 101 1x3'
> ,
> disk_io = 'none'
> ,
> nstep = 1000
> ,
> /
>
> &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'
> ,
> /
>
> ATOMIC_SPECIES
>
> Ti 47.86700
> Ti.pw91-sp-van_ak.UPF
> O 15.99940
> O.pw91-van_ak.UPF
> ATOMIC_POSITIONS
> crystal
> Ti 0.79001 0.05515 0.04075 0 0 0
> Ti 0.92677 0.05515 0.23765 1 1 1
> Ti 0.29001 0.22181 0.04075 0 0 0
> Ti 0.42677 0.22181 0.23765 1 1 1
> Ti 0.57420 0.22181 0.08998 0 0 0
> Ti 0.71096 0.22181 0.28687 1 1 1
> Ti 0.07420 0.05515 0.08998 0 0 0
> Ti 0.21096 0.05515 0.28687 1 1 1
> O 0.61134 0.05515 0.08150 0 0 0
> O 0.74810 0.05515 0.27840 1 1 1
> O 0.11134 0.22181 0.08150 0 0 0
> O 0.24810 0.22181 0.27840 1 1 1
> O 0.39553 0.22181 0.13073 0 0 0
> O 0.53229 0.22181 0.32763 1 1 1
> O 0.89553 0.05515 0.13073 0 0 0
> O 0.03229 0.05515 0.32763 1 1 1
> O 0.25286 0.05515 0.04922 0 0 0
> O 0.38962 0.05515 0.24612 1 1 1
> O 0.75286 0.22181 0.04922 0 0 0
> O 0.88962 0.22181 0.24612 1 1 1
> O 0.46867 0.22181 0.00000 0 0 0
> O 0.60543 0.22181 0.19690 1 1 1
> O 0.96867 0.05515 0.00000 0 0 0
> O 0.10543 0.05515 0.19690 1 1 1
> Ti 0.79001 0.38848 0.04075 0 0 0
> Ti 0.92677 0.38848 0.23765 1 1 1
> Ti 0.29001 0.55515 0.04075 0 0 0
> Ti 0.42677 0.55515 0.23765 1 1 1
> Ti 0.57420 0.55515 0.08998 0 0 0
> Ti 0.71096 0.55515 0.28687 1 1 1
> Ti 0.07420 0.38848 0.08998 0 0 0
> Ti 0.21096 0.38848 0.28687 1 1 1
> O 0.61134 0.38848 0.08150 0 0 0
> O 0.74810 0.38848 0.27840 1 1 1
> O 0.11134 0.55515 0.08150 0 0 0
> O 0.24810 0.55515 0.27840 1 1 1
> O 0.39553 0.55515 0.13073 0 0 0
> #O 0.53229 0.55515 0.32763 1 1 1
> O 0.89553 0.38848 0.13073 0 0 0
> O 0.03229 0.38848 0.32763 1 1 1
> O 0.25286 0.38848 0.04922 0 0 0
> O 0.38962 0.38848 0.24612 1 1 1
> O 0.75286 0.55515 0.04922 0 0 0
> O 0.88962 0.55515 0.24612 1 1 1
> O 0.46867 0.55515 0.00000 0 0 0
> O 0.60543 0.55515 0.19690 1 1 1
> O 0.96867 0.38848 0.00000 0 0 0
> O 0.10543 0.38848 0.19690 1 1 1
> Ti 0.79001 0.72181 0.04075 0 0 0
> Ti 0.92677 0.72181 0.23765 1 1 1
> Ti 0.29001 0.88848 0.04075 0 0 0
> Ti 0.42677 0.88848 0.23765 1 1 1
> Ti 0.57420 0.88848 0.08998 0 0 0
> Ti 0.71096 0.88848 0.28687 1 1 1
> Ti 0.07420 0.72181 0.08998 0 0 0
> Ti 0.21096 0.72181 0.28687 1 1 1
> O 0.61134 0.72181 0.08150 0 0 0
> O 0.74810 0.72181 0.27840 1 1 1
> O 0.11134 0.88848 0.08150 0 0 0
> O 0.24810 0.88848 0.27840 1 1 1
> O 0.39553 0.88848 0.13073 0 0 0
> O 0.53229 0.88848 0.32763 1 1 1
> O 0.89553 0.72181 0.13073 0 0 0
> O 0.03229 0.72181 0.32763 1 1 1
> O 0.25286 0.72181 0.04922 0 0 0
> O 0.38962 0.72181 0.24612 1 1 1
> O 0.75286 0.88848 0.04922 0 0 0
> O 0.88962 0.88848 0.24612 1 1 1
> O 0.46867 0.88848 0.00000 0 0 0
> O 0.60543 0.88848 0.19690 1 1 1
> O 0.96867 0.72181 0.00000 0 0 0
> O 0.10543 0.72181 0.19690 1 1 1
> K_POINTS gamma
>
> --
> ==================================================================================
> 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
> ******************************************************************************************************************
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