Really thanks for your suggestion Giovanni, I just have few more doubts that if i want to find the work function of Au-ZnO Slab. I have created Au(111) and ZnO(0001) Slab. So it has an interface of Zn-Au and a vacuum of 10 Angstrom. I took 6 layers of Au and 4 double layers of ZnO. Then how to proceed. Means 1) Which two consecutive atomic planes I have to choose Au-Au, Au-Zn or the Zn-O planes. for the microscopic average calculation?
2) Also in-order to choose the inner part of the slab, so that part is inside the Au-Slab or the ZnO Slab? regards On Wed, Mar 18, 2015 at 5:02 PM, Giovanni Cantele < [email protected]> wrote: > The average electrostatic potential you are calculating/plotting does show > microscopic oscillations, revealing the atomic planes > (plot the 2d column of reference/Al100.avg.out as a function of the 1st > one). > > The calculation of the work function requires a “constant” energy level to > compare the bulk and the slab calculation. For this purpose, > you run a macroscopic average of the x-y averaged electrostatic potential. > The window you choose for the macroscopic average > is just the distance between two consecutive atomic planes (in a.u.). > Because the input positions are in alat units, you get > > (2.8284271247461898 - 2.1213203435596428) * 5.4235090117 = 3.835 > > In this way, microscopic oscillations with period 3.835 are averaged and a > constant level (in the inner region of the slab) is obtained. > > Concerning 17.8087, in order to get this constant value, you can choose > any position in the inner part of the slab where the > macroscopic average does not show significant variations. > > Giovanni > > > On 18 Mar 2015, at 10:49, Bipul Rakshit <[email protected]> wrote: > > In espresso, there is an example to find the workfunction of Al. In the > run_example, the input for the the macroscopic average is the following > cat > Al100.avg.in <http://al100.avg.in/> <<EOF > 1 > Al100.pot > 1.D0 > 1440 > 3 > 3.835000000 > EOF > > In this file the quantity "3.835" i saw in average.f90 as "awin ! > the size of the window for macroscopic averages" > > So my doubt is how we can choose this no. Can we get the information from > another file prerun file, like Al100.pot, or something else. > > Also in run_example there is another quantity vSlab > > vSlab=`grep "17.8087" Al100.avg.out | cut -d \ -f 10` > > So how the value correspond to "17.8087" is assign as vSlab? > > Kindly help me in this matter. > > regards > -- > Dr. Bipul Rakshit > Research Associate, > Institute of Physics (IOP), > Bhubaneswar- 751 005 > Orissa > India > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum > > > -- > > Giovanni Cantele, PhD > CNR-SPIN > c/o Dipartimento di Fisica > Universita' di Napoli "Federico II" > Complesso Universitario M. S. Angelo - Ed. 6 > Via Cintia, I-80126, Napoli, Italy > e-mail: [email protected] > Phone: +39 081 676910 > Skype contact: giocan74 > > ResearcherID: http://www.researcherid.com/rid/A-1951-2009 > Web page: http://people.na.infn.it/~cantele > > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum > -- Dr. Bipul Rakshit Research Associate, Institute of Physics (IOP), Bhubaneswar- 751 005 Orissa India
_______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
