Dear Abdul Moyez ,

according your 'Skills and expertise' from your RG homepage one should expect that you are familiar with the Bragg law*):

n*lambda= 2 * d * sin(theta)

Differentiating this relation will give you:

0 = 2* delta_d*sin(theta) + 2*d*cos(theta)*delta_theta

Here you have the relation between the peak shift delta _theta and the d-shift delta_d.

You may solve for delta_d by yourself.

Please pay attention to the signs:

left shift of the peak (lower theta) will give higher d-spacing... and vice versa

*) https://en.wikipedia.org/wiki/Bragg%27s_law

Best regards

G.M.

Dear Gerhard Martens as theta will decrease d value will increase. For exact calculation you can solve it by bragg's law.

The best answer is given by Professor Gerhard Martens.

Thank you a lot for good experience and valuable answering.

Dear Nitin Kumar ,

you may accidently have addressed me instead of Abdul Moyez .

I myself know how to deal with the Bragg law as you can see from my answer above.

Additional remark:

The crystallite size/peak width (as mentioned in the question above) has no impact onto the d theta relation (Bragg law).

By Bragg's law

nλ = 2d sinθ

d = nλ/2 sinθ

where n = 1 for any materails

therefore d = λ/2 sinθ

here θ = mean peak position (half of 2θ)

For this, please check the article, DOI: 10.13140/RG.2.2.27720.65287/3