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Topic: Xray diffraction interpretation  (Read 1270 times)

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Offline tulip11

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Xray diffraction interpretation
« on: October 19, 2017, 08:31:52 AM »
I'm trying to interpret an x ray diffraction pattern. So far ive read the 2θ angles, calculated the d spacing and the values of 1/d2 and the ratio of 1/d2 to that of peak 1 to gain h2 + k2 + l2. For most results i've got interger values as expected so have been able to assign miller indicies. However for one of the results i've gained a value of 3.6 for h2 + k2 + l2. I have no idea what to do with this results and have tried to find the anser online but cannpt find it anywhere. I though perhaps i could double it to get a value of ~7 but have no idea if this would be right.  If anyone could point me in the right direction that would be great.

Offline Corribus

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Re: Xray diffraction interpretation
« Reply #1 on: October 19, 2017, 09:31:36 AM »
A little more information on what you are doing would be helpful.
3.6 is reasonably close to 4. Are you sure there isn't an error somewhere in your measurement?
You shouldn't just double values without reason to do so.
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline tulip11

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Re: Xray diffraction interpretation
« Reply #2 on: October 19, 2017, 09:54:39 AM »
A little more information on what you are doing would be helpful.
3.6 is reasonably close to 4. Are you sure there isn't an error somewhere in your measurement?
You shouldn't just double values without reason to do so.

Im trying to work out the x value in NaxWO3 from the unit cell parameter. But to get the unit cell parameter you take dhkl×sqrt(h2 +etc). I'm also trying to get the miller indicies of (h k l) which obviously requires that the square summed needs to be an integer value.
I've redone the calculations to get 3.6 several times so i'm sure that its not a calculation error. All the other values came out to within 0.05 of an integer so it just seemed like it was out too far to round..

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