you use the atomic% and change the fraction to integers. 40% Fe and 60% O means Fe2O3 . I didn't I understand your questions correctly?

Thank you.

may be I should mention stoichiometry instead of composition.

Dear Gert Nolze,

I have 4 elements in my compound.

I got atomic %'s as following

7.82 %

15.15 %

21.89 %

55.14 %

how to verify the stoichiometry?

A?B?C?D?

I have calculated as

15.15/7.82 = 1.937

21.89/7.82 = 2.799

55.14/7.82 = 7.05

so, A1B1.937C2.799C7.05

is this correct method? otherwise can you please explain?

thank you

Dear Poojitha,

Quantification from EDS data is a little tricky thing. Owing to several factors (including the validity of ZAF correction factors), your quantification may have errors. Ideal would be to carry out EPMA which has a better accuracy. 

But, on the other hand, of course you can get a rough estimate and predict roughly what could be the phase as Prof Gert suggested.  But have a idea about the elements and the X-ray lines of interest and accordingly pay attention while choosing the Accelerating Voltage. 

Good luck. 

In fact, you applied the mathematics correctly. However, as you also realized, the numbers are quite "strange". The reason is explained by Raghavendra K G: measurement errors and unsufficient correction terms. On the other hand, EDX or even EPMA results can only give a glue about the approximate composition. The major requirement are of course that your material is homogeneous and stable in vacuum and during electron bombardment. Using your results I would assume a phase AB2C3D7. But it can be also A(B,C)5 D7.....or anything else...

In order to discuss this further you should tell us, which element did you measure. Also their reliability is different i.e. the errors can be much bigger for some elements compared to others.

Ok.

The elements are Y , Ba, Cu , O 

I think Gert's phase assumption of YBa2Cu3O7 is spot on! It means there may be issues with your data. Can you show us your spectrum and resultant data table? Is this a single spot, an area, or average of multiple spots?

I have 2 element in my compound . ( i synthesized V2O5)

i.e. V= 28.47%

O = 71. 53

how to confirm the ratio of V and O in my compound.

@ J. Zia: you should ask a new question :-). otherwise nobody will find this since it is 2 years old already...

please see the answer to your query

Bommareddy Poojitha

exact percentage composition could be find out by ICP-AES.

Jannatun Zia

Santanu Kumar Padhi But how did you measure the composition, suppose here in your pdf you have shown How did you surface composition CuO+CeO2. What are ABCD in your case. why Au?