[Wien] How to get exact 25% doping ?

Dear community Fellows I created a 2*2*2 supercell and got 31 Cd atoms. I want to replace Cd atoms by Zn atoms so that to get 25% of doping. 25% of 31 atoms is 7.75 which is not a whole number. How to obtain whole number to get exact 25% of doping ?. Thank You All Naseem

Re: [Wien] How to get exact 25% doping ?

It's not possible to get 31 atoms in a 2*2*2 supercell, unless you manually removed one. I guess it should be 32 in your case. On Sun, 25 May 2014, Naseem Hassan wrote: Dear community Fellows I created a 2*2*2 supercell and got 31 Cd atoms. I want to replace Cd atoms by Zn atoms so that to

Re: [Wien] How to get exact 25% doping ?

Yep 31 atoms are not possible in 2*2*2 supercell. I think there should be 64 atoms (replace 8 atoms for 25% doping), as in 1*1*1 supercell 8 atoms(replace 1 atom), in 2*1*1 supercell 16 atoms (replace 2 atoms) and in 2*2*1 super cell 32 atoms (replace 4 atoms). On Sun, May 25, 2014 at 4:44 AM,