You can not solve a structure with Rietveld, only refine it. First you have to create a reflection file (*.hkl) from your powder profile (for instance with Jana2006 software). Then you can try to solve this with shelx (direct methods) or Jana2006 Superflip routine. Do you have an idea about the structure type?

Edit: Try EXPO software.

Rico is correct, you only refine data with Rietveld refinement. You can solve for the structure if you have software such as Crystal Match! with a relevant database such as PDF-2 or PDF-2 (Powder diffraction files); which then attempt to profile fit your data to the existing entries in the database.

If your material is new, then these may not exist - thus you would then have to follow Rico's second suggestion and build a reflection file from your data in order to calculate the structure.

This could also change with temperature - so you would need to make more XRD measurements at elevated temperatures in order to see where these changes occur. A good starting point is to use TG-DSC, as this should give you the endothermic / exothermic peaks where the temperature corresponds to any internal changes in the material, then focus upon these transition temperatures with your XRD study. 

Thank you so much.

I have synthesize Bi2M2O7 and used shaari paper that reported the synthesis previously. Its structure is fd3m cubic with a=10.27 A. Pleas find the attached file and compare it with the paper and help me and suggest a method.

Thank you

As far as I remember, componds like this should have pyrochlore-type structure. Try to use Bi2Ti2O7 as initial model for Rietveld refinement.

Thank you Dear MISSYUL. My problem isthat I have no experience to work with rietvel refinement.

Is it possible to help me to refine the structure?

Thank you

I briefly looked at your powder pattern. It is definitely not cubic pyrochlore phase. And most likely even not single phase. So try to do search with PDF database, probably you will find something else that fits your data.

Also, you will need better quality of measurement for the structure analysis when you obtain what you expected.

Thank you so much alexander. However, I had referenced to shaari paper that attached in this section and the peaks are the same as he reported. How do you think about the synthesized pahse for shaari?

How did you conclude that the phase is not cubic and pyrochlore?

Dear Shahin this is my analysis.

Dear Stefano. Thank you so much for the analysis. I will be very thankful if you explain more from the analysis for me (software, space group, crystal structure, purity and ...because I have no experience) and send a higher resolution image for me via email:[email protected].

sincerely yours

shahin khademinia

Dear Stefano. Is it possible for you to analysis the attached files for the compound(Bi2Mn2O7)? I have examined with the other methods.

Thank you so much for the helps

Dear Shahin, I see that you already got full analysis for your file. I attach here comparison of your data with structure model for Bi2Mn2O7 (using your hypothesis about lattice parameter and atomic positions for Bi2Ti2O7).

Space group should be Fd-3m.

Hello dear murat. Yes space group is fd-3m. I want to know If the phase has been synthesized?even non pure phase? And if shaari paper shows the Bi2Mn2O7 phase?

Thank you for your response

Dear alexander. can you send to me the (space group, software, the theoretical pattern separately,...). And if I have synthesize the material? Please compare it with shaari paper that I attached above.

Thank you

Attached file is a fullprof pcr file if you find someone to show you how it works. It contains two phases and can help you for a simple profile matching process.

i)Bi2Mn2O7

ii)Bi2O3

You should copy and paste it to a notepad and save as pcr file.

Dear murat. I converted it however, at this time (summer) there is no one to help me. Is it possible to help me to have a picture of the analysis separately to send them to referee. And If I have synthesized the material successfully?

Thank you so much

Hello Dear Shahin.

I found that: your sample contains two phases:

i)Bi2Mn2O7 phase with space group F d -3 m

a=b=c=10.325376 Angström

alpha=beta=gamma=90.000000

ii)Bi2O3 phase with space group P 21/c

a=5.842770 b=8.147644 c=7.498813 Angström

alpha=90.000000 beta=113.024078 gamma=90.000000

Analysis is done in FullProf with a Chi^2 of 6.7 in profile matching mode. 

Best wishes.

Hello, dear murat. You made me very happy. please explain about the blue and red bars. Also, explain about the Bi2O3 impurity phases and is it possible to make miller indices for the pyrochlore phase?

I have examined the synthesis via another method. Iattached the xrd file. please do the analysis for it

Thank you so much

Hello, dear please send to me a paper until I can report the data according to it.

Thank you

 Shahin Khademinia, ihave seen your paper

http://jmatpro.iaun.ac.ir/pdf_8660_ce6fab85dd697ae5e729a22ca49636c8.html

you have used fullprof for refinement. Can you please tell me the ATZ value you got? (Bi2Mn2O7)

Hello, The work was performed by Dr. MURAT SERTKOL who is an expert in the field you can search his name in the site.