Messages

1

General Questions and Answers / About Random alloys and substitutional alloy feature

« on: December 12, 2019, 06:31 »

Hello Sir,
I want to make Cd0.9Zn0.1Te random alloy with substitutional alloy feature.
My question is if I add CdTe from database with only two atoms(one Cd and one Te) and substitute Zn 10% by selecting Cd atom. Than, it will act as Cd0.9Zn0.1Te
Or do I have to repeat it in all directions to see the changes.
Basically, I do want to increase number of atoms for which I added CdTe from database and repeated it with A=5,B=2,C=1 and substituted one Cd atom with Zn which resulted in Cd0.9Zn0.1Te with only total 20 numbers of atoms but this resulted in changing of FCC structure into something of known.
And, when I performed Bandstructure analysis on it after optimization, bandgap came out to be 1.9 eV with MGGA PBE, which is not matching to practical values of 1.54eV.
So, how does this substitutional alloy feature work?
And, how should I perform Bandstructure analysis to get results close to practical values?
Thanks in advance , Sir.

2

General Questions and Answers / Re: Brillouin Zone route of Heterostructures

« on: December 6, 2019, 17:22 »

Thank you sir for your reply!
But my exact problem is as, at first I made Cd(0.9)Zn(0.1)Te with total 20 number of atoms by repeating CdTe in "A=5, B=2, C=1" and substituting one Cd atom into Zn.
So, when I'm seeing the unit cell with Brillouin Zone Veiwer feature available in VNL. It isn't matching to any of the predefined Bravais Lattice and some of the extreme points aren't even on the edges of shape.
So, my exact question is, how should i define Brillouin Zone for my CdZnTe for bandstructure analysis.
And, this is the same problem that I'm getting for my heterostructure as well.
Thanks in advance, Sir.

3

General Questions and Answers / Brillouin Zone route of Heterostructures

« on: December 3, 2019, 15:08 »

Hello ,
I am not able to define the brillouin zone for the calculating the band structure of the heterostructure  of MoS2 and CdZnTe. Should we define the heterostructure as per  the lattice type (BCC, FCC, hexagonal, etc) or is there other method in atk to define the brillouin zone as given in atk tutorials for calculating the bandstructure?