Re: [PyMca] Fuel Cell XRF: Concentration Error and Matrix Definition

[PyMca g. p. m. list. <pym...@li...>]

Dear Aixeen,

On 23/07/2023 19:30, PyMca general purpose mailing list. via PyMca-users 
wrote:
>
> We wanted to clarify the following questions that arose while we were 
> using PyMCA.
> We are having some troubles/doubts in defining the matrix due to the 
> fact that we cannot fully pinpoint the compositions of the sample.
>       1. Since the sample is not simply just pure elements but are 
> mixed with other components in different layers of varying thickness, 
> and with unknown concentration of the membrane at the middle of the 
> cathode and anode, we opted to use just a simple layer. We implemented 
> the single layer setup for the fit as a strategy. However, how do we 
> correctly define the matrix? In the single layer setup, it asks for 
> the completing material to be used.  What does completing material 
> mean/refer to? What would this be for our case? Should it be the whole 
> sample?


If you have a multilayer, you have to use a multilayer unless everything 
can be considered a thin sample.


For the rest, without knowing your system, I cannot say much.


 From your mail, one does not know if your anode is pure Pt or Pt 
deposited on a support. Besides that, I have no idea about how accurate 
is the description of the emission profile of your X-ray tube. Even 
having the spectrum to check for big discrepancies in the K-alpha and 
K-beta ratios could help on figuring out if there big mistakes on the 
setup description.


Best regards,


Armando