We have a new XRD equipment with a Cobalt generator.
How can one change the raw file output from the software so that analysis can be done with softwares which take standard values correlated to Cu generators.
I have tried that with powdll by changing the wavelength, but it is only changing the wavelength, and not changing the y axis values to suit Cu target values.
It will be a cobalt anode tube rather than a cobalt generator. The generator simply supplies power to a tube, and the tube can be any anode material. We have both Cu and Co on two different instruments here.
It is necessary to set up the wavelength used in the configuration software for the diffractometer before the data are collected. This will then write the wavelength used to the header of all data files which is picked up by interpretation software.
All your peak positions will now be different from those measured using Cu but all the d-spacings will be correct. Get used to seeing the peaks in a different position!! The interpretation software uses the d-spacings rather than 2-theta values as they are wavelength independent, so all data analysis can be done without worrying about the wavelength.
You say "changing the y axis values" - the y axis only contains counts (or counts per second) intensity and has nothing to do with the wavelength.
Thank you Dr. Slipper. I was in deed incorrect in mentioning those tubes as generators.
I do not possess an XRD, but my department has two of them. The older one is with a Cu tube and we are accustomed with it. Some of us had been using Philips XPert and some other were using Maud. We have a certain conviction that these analysis software are calibrated for results from Cu tube equipment. Recently we have acquired a new XRD with a Co tube. The peaks are shifting(obviously).
I understand that the peaks are only shifted, the d spacings remaining same. Reading some of the posts in researchgate I had adjusted the 2 theta values (with a formula :
new 2theta = 114.59156 * asin((L2/L1)*Sin(0.00872664 * (old 2theta))
If I want to analyze the Co tube result, should I follow the path I have stated, or should I proceed as usually we do with Cu tube result.
I think there is little point in converting the data. The software should handle the Co data just as well as the Cu. Try it first with a simple system. The only reason do it might be if you needed to graphically compare data from old and new instruments.
As per your advice, I tried it without conversion. The approach did not work out in the first instance. But there is an option to go in to
Edit selected data -> General -> Edit -> Source -> Option > Cobalt K alpha.
Now it worked. The software (Maud) defaults to Copper, that is why the problem in the beginning came. Now it is fine. Thank you Dr. Slipper.
best regards.
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