Chemical Forums
Specialty Chemistry Forums => Nuclear Chemistry and Radiochemistry Forum => Topic started by: kingpharaoh on April 19, 2014, 04:25:21 AM
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Hello all!
I find myself struggling to understand some questions relating to synchrotron xray diffraction. The first question goes as follows:
What are the advantages of using relatively high energy X-rays (λ=0.5Å) as available at the synchrotron over using a conventional Cu X-ray source (λ=1.5406Å)?
The only advantages that I know of include:
(1) Gives a higher resolution due to synchrotron being orders of magnitudes brighter than other conventional sources which leads to do quick experiments even on small samples.
(2) It has a longer spectrum ranging from infrared to hard x-rays.
But I feel like my answers are not quite enough to answer the question yet.
Second question goes as follows:
Why is the intensity of the high angle diffraction peaks so much greater in the pattern measured at 100 K than in that measured at 300 K?
A very similar pattern can be seen here: http://www.intechopen.com/source/html/18055/media/image31.png (http://www.intechopen.com/source/html/18055/media/image31.png)
Just replace 67K by 100K.
Unfortunately for this question, I have absolutely no valid reasoning to give on how this works. So I would really really need help on this one.
Thanks for taking the time to read my question and I hope you can share with me some insight on how I can go on with answering the question!
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I think your answer to question 1 is a combination of two ideas. One is that the higher intensity of the beam leads to shorter experiment times. But the question of differences in wavelength is a separate issue IMO. I think resolution might be on the right track, but I am not a professional crystallographer.