Question

Fluorescent occurs when the radiation in the primary beam knocks out___________

(a) Outer shell electrons

(b) Inner shell electrons

(c) Outer shell photon

(d) Inner shell photon

I had been asked this question in unit test.

Origin of the question is Sources of Background Radiation Fluorescence topic in division X-Ray Diffraction of Solid State Chemistry

Answer 1

Right option is (b) Inner shell electrons

The best I can explain: Fluorescent occurs when the radiation in the primary beam that is emitted by the copper target knocks out inner shell electrons within atoms of the sample. Electrons in the outer shells drop down to occupy empty levels in the inner shells and in so doing they emit their excess energy in the form of X-rays.