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QuantumATK => General Questions and Answers => Topic started by: ankitmaahich on December 12, 2019, 06:31

Title: About Random alloys and substitutional alloy feature
Post by: ankitmaahich 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.