wavelenght issue!

[Tamas Dragos]

Perhapse I did not make myself clear so I’ll just try again. I know how to set up the wavelengths in FullProf and I also know how to setup the ratio, but a ratio of 0.5 seems so far away from the real physical value. It is not so easy to calculate a mean wavelength and I do not think that FullProf just takes the simple mean of the two wavelengths meaning wavelenght1 + wavelength 2 / 2. So I want to know if I wanna calculate the values for the cell parameters with another method, how do I do to find out which value FullProf uses as a mean for the kalpha1 and kalpha2 wavelenghts.    Thank you Mr. Miguel Hesiquio-Garduño for your help but that wasn’t what I asked.