what is the relation between an angle and interplanar spacing? What will happen to the unit cell volume? What is the relation between strain and interplanar spacing?
Dear Ummer Altaf ,
please get familiar with the Bragg law...
It relates the interplanar distance d and the sine of the diffraction angle (commonly denoted as theta) to the wave length lambda of the diffracted x-rays in use.
lambda= 2*d*sin(theta)
This law will answer all your questions...
For details please have for example a look at:
https://en.wikipedia.org/wiki/Bragg%27s_law
But I wonder, that, according to your skills and expertise, you are familar with various aspects of quantum physics as well as on theoretical physics, but not on such a basic equation like the Bragg law, which should be part of basic physics courses.
Apart from the sample properties, experimental issues may also cause peak shifts; you may have a look for example at the answers of a similar question from many years ago here on RG:
https://www.researchgate.net/post/Why_do_XRD_diffraction_peaks_shift_towards_low_theta_value
Good luck with your research and stay healthy;
best regards
G.M.
This because of Bragg law (lambda= 2*d*sin(theta)) which mentions that increasing d space leads to decreasing the angle and decreasing d space leads to increasing the angle.
Aa I wrote previously , mechanical strains of tension and compression in bulk materials, their doping heating, and radiation treatment can be followed by broadening and shifts of XRD peaks in different ways. Simply according to Cosine low or in dependence on possible distortions of crystal lattice.
When lattice expands due to some heating because of the X-ray falling on the sample also may be a reason for the XRD peak shifting towards the left side.
Dear Dharmadoss Sornadurai ,
nice idea (thus a recommendation from my side)
but do you have ever estimated the increase of temperature due to x-ray exposure?
Let us take for example water exposed to 1Gray of x-ray dose.
1Gray is eqaul to an energy deposition of 1J/kg ~ 0,23cal/kg=~0,23 *10-3cal/g.
For water we have a heat capacity if about 1cal/K.
So 1 Gray will increase the temperature of water by about 2,3*10-4K.
Thus an increase of lattice constants to be 'seen' by XRD via thermal expansion, which is in the order of about 10-5/K (solid state), is very, very unlikely...
Best regards
G.M.
Try to link with the Debye Waller factor and try to interpret the peak shifting,
What about soft conensed materials ? like organic and biomaterials ?
It is related with the Braggs law relation as it is answered in above explanations by various members. However, it also gives the blue shift and red shift by which crystal quality and other details can be calculated. For more details, refer my e-papers on the ResearchGate.
Try re-align your instrument with the standard samples. Then carry out your actual samples.
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