It is very simple to perform Rietveld refinement of doped samples, if you know refinement of undoped. As you already accepted that you know the refinement of undoped/parent samples. Then for doped samples you have to add dopant atoms or ions and change the occupancy in the proportion of dopant site. Say your system is ABO3 cubic perovskite with occupancy of 1, 1 & 3 of A, B & O, respectively. The after doping of C at B-site; system becomes AB1-xCxO3, then use occupancy 1, 1-x, x & 3 of A, B, C & O, respectively. The coordinates and thermal coefficients of C will be same as B. I hope, it will be understandable for you and you will be benifited from it.

Best of luck

you should add your doping element in .PCR file and add new occupancy number in the same percentage with doping as detail given by Mr. Dinesh Kumar. One thing is very important that before refine you must fixed all parameters and start refine with background one by one carefully otherwise your file can be damaged.

Dinesh Kumar, Anand Somvanshi Thank you very much.

I am working with BaFe12O19. And my doped sample is BaFe11.7Zn0.3O19. How can I edit the occupancy number, as there are five different Iron atoms. Thank you in advance. Anand Somvanshi Anand Somvanshi Dinesh Kumar Dinesh Kumar

I use FullProf so this "how to" is specific to the format that FullProf uses for (.pcr) files (and specific to the elements in my structure).

Copy and paste this into a text editor so it is easier to see what is going on.

First, consider the case where you have an idea of the doping percentage (in my case, 12%Ge and 88%Si), but you want to adjust the occupancy of the semiconductor (Si + Ge) relative to the other atoms.

The section of your (.pcr) file corresponding to the atomic positions/occupancies should look like:

*-v--------------------------------------------------------------------------------

!Atom Typ X Y Z Biso Occ In Fin N_t Spc /Codes

Yb1 Yb 0.17753 0.67753 0.50000 0.42637 0.25000 0 0 0 0

0.00 0.00 0.00 0.00 11.00

Al1 Al 0.00000 0.00000 0.00000 0.66324 0.12500 0 0 0 0

0.00 0.00 0.00 0.00 21.00

Si1 Si 0.37298 0.87298 0.00000 0.48164 0.22000 0 0 0 0

0.00 0.00 0.00 0.00 30.88

Ge1 Ge 0.37298 0.87298 0.00000 0.40000 0.03000 0 0 0 0

0.00 0.00 0.00 0.00 30.12

*-^--------------------------------------------------------------------------------

Pay attention to the numbers (30.88) and (30.12).

Since both start with (3), they are constrained in relation to each other.

Then, since Si is 88%, I put 0.88 and since Ge is 12% I put 0.12.

Second, consider the case where you know how much semiconductor is mixed with the other atoms, but you do not know the doping%.

The section of your (.pcr) file corresponding to the atomic positions/occupancies should look like:

*-v--------------------------------------------------------------------------------

!Atom Typ X Y Z Biso Occ In Fin N_t Spc /Codes

Yb1 Yb 0.17753 0.67753 0.50000 0.42637 0.25000 0 0 0 0

0.00 0.00 0.00 0.00 0.00

Al1 Al 0.00000 0.00000 0.00000 0.66324 0.12500 0 0 0 0

0.00 0.00 0.00 0.00 0.00

Si1 Si 0.37298 0.87298 0.00000 0.48164 0.22000 0 0 0 0

0.00 0.00 0.00 0.00 11.00

Ge1 Ge 0.37298 0.87298 0.00000 0.40000 0.03000 0 0 0 0

0.00 0.00 0.00 0.00 -11.00

*-^--------------------------------------------------------------------------------

The pattern is similar to above, but note that the other elements' occupancies are not varied (0.00) and since Si and Ge are the only parameters varied, there is (1x.xx) in front of them.

For each increment in Si, there is an equal but negative increment in Ge so the amount of semiconductor relative to everything else is constant (since everyhting else is held fixed).

PLEASE comment if there are any mistakes or if something is confusing. I almost posted this without putting a (-) in front of the (11.00) at the end.

How to do Rietveld refinement for the doped sample -Reg

I have completed the refinement for the pure sample and i have all refinement parameters and the refined occupancy. I have doped one element in ABO3 sample then after doping of C at A-site the system becomes A1-xCxBO3 . I also know the lattices parameter and the occupancy of the C element, now i don't know how at add the c element in the refinement. Kindly any one say me the steps to follow for refining the doped sample. Liam Scanlon Anand Somvanshi Md Saiful Alam Dinesh Kumar

Add a extra number of atom with the same X, Y, Z, position of the atom, on which side you are doping your new element but you have to change occupancy of both elements according to the percentage of dopant.

Anand Somvanshi thanks sir for your reply. I will carry out as per your suggestion sir.

Dear Bharath Sabarish V.C you can follow https://www.youtube.com/watch?v=0TxeHP3NE2Y link.

thanks sir for the link Md Saiful Alam