Dear Reshma Kuppili You have to try different concentration at particular site for example barium site or titanium site. Some may form a structure and some may not.
I think you can do, EDX on multiple locations and compare the at%/mol%/wt% of doped atom with that of theoretical one. You may not get an exact amount, but you get a range...
Reshma Kuppili, you can perform ICP-OES/ICP-AES/ICP-MS to get the exact composition of each element in your material. Else, you can perform Rietveld analysis using Fullprof software to get the exact composition.