Question

In the powder diffractometer, the counter is set, the counter is set to scan at a ________

(a) Variable temperature

(b) Constant temperature

(c) Constant angular velocity

(d) Variable angular velocity

I have been asked this question during an interview.

I'd like to ask this question from Modern X-Ray Powder Techniques and their Applications topic in division X-Ray Diffraction of Solid State Chemistry

Answer 1

Right answer is (c) Constant angular velocity

To explain: In normal use, the counter in the powder diffractometer is set to scam over a range of 2Θ values at a constant angular velocity, it is common practice to refer to the angle 2Θ between the diffracted and undiffracted beams, rather than to the Bragg angle, Θ.