A possible reason is the presence of K(alfa2) or K(beta) wavelengthes in the spectrum of the x-ray beam of your XRD equipment. Try to adjust monochromator.

A possible reason is the presence of K(alfa2) or K(beta) wavelengthes in the spectrum of the x-ray beam of your XRD equipment. Try to adjust monochromator.

Apparently, it seems that the FWHM of the new peaks are different from the pattern, so the new peak are probably not from your material. It is the same substrate holder ? The width of your beam might be larger on your new setup and can record signal from the substrate holder or undesired materials (we had the same problem on our diffractometer).

Regards,

Emile HAYE

With XRD as the gold standard for crystals, the changes you are seeing in the patterns are real, why not try using a different technique e.g. FTIR and phonon-mode Raman spectroscopy to cross-check?

I agree with Dmitrii Irzhak and it could look like mostly Cu K-beta radiation contamination. Cu K-beta is filtered out using a nickel filter. See if this has been removed from your beam or if it needs to be replaced.

I am also agree with Dmitri Irzhak due Cu radiation it depends on the type of alpha or beta.

Check the holder material and size of irradiated area, and compare them in old and new machine. K (beta) is much smaller than K(alpha), and has lower 2theta position.

Dear Tony Ch ,

I think now it is time for me to enter the discussion by words and not only by recommendations:

a) The statement from above: ‚the additional lines are propably due to K-beta line of the x-ray tube‘ is right. Moreover, as we will see below, the additional lines are in fact due to the K-beta line contribution of the primary x-ray spectrum of the x-ray tube.

b) It is right, that the K-beta line contribution of the XRD pattern can be significantly reduced by a Ni filter of appropriate thickness (Ni K-edge is just in between the Cu K-alpha and the Cu K-beta line(s)).

c) The statement 'XRD peaks due to K-beta are higher in 2theta position compared to K-alpha peaks‘ is wrong.

Especially Tony Ch, please pay attention and try to follow the calculations below:

So let us have a look at the Bragg law, which connects the wave length lambda (of K-apha and K-beta) to the theta value of the XRD peaks:

For first order diffraction we have:

lambda = 2*d* sin(theta) with d as the distance of the involved reflection planes.

(Please note, that the diffraction pattern are commonly presented in 2theta scale)

The Bragg law is valid for K-alpha as well as for K-beta lines.

So we have:

lambdaK-alpha = 2*d* sin(thetaK-alpha) and lambdaK-beta = 2*d*sin(thetaK-beta)

from this set of equations we get:

lambdaK-alpha/lambdaK-beta = sin(thetaK-alpha)/sin(thetaK-beta)

and from that:

sin(thetaK-beta)= sin(thetaK-alpha)* lambdaK-beta/lambdaK-alpha

For the wave lengths Cu K-alpha = 1,54A and Cu K-beta=1,39A we have:

sin(thetaK-beta) = 0,903*sin(thetaK-alpha)

Here we see that the thetaK-beta position (and thus the 2thetaK-beta value) is smaller than the thetaK-alpha peak position.

For the main peaks of the XRD pattern (given by Tony above), I have calculated the K-beta positions and inserted them in his XRD diagram; please see the attached file.

The beta peak positions very nicely coincide with the new upcoming peaks marked by Tony’s red asterisks.

Moreover, also all main peaks around 35°(in 2theta) have got their K-beta equivalents too.

Is there any more evidence necessary………

проверьте кювету для образца, или держатель. Скорей всего они пластмассовые, а ваша новая машина лучше считывает небольшие пики от них. Но сами пики можно отнести к азотсодержащему углероду. Аналогичные пики появляются при легировании азотом графита

Dear Victorya A. Chaika ,

your papers are written in english but here your answer is written in russian letters.

Please answer in english, so we can all benfit from it...

Thanks in advance and best regards

check the sample cuvette, or holder. Most likely they are plastic, and your new car is better at reading small peaks from them. But the peaks themselves can be attributed to nitrogen-containing carbon. Similar peaks appear when doped with graphite nitrogen.