Question

Which of the following system will not show ESR spectra

Answer 1

Explanation:

the following species may show an ESR spectrum: (i) Free radicals having odd number of electrons (ii) Odd electron molecules, e.g. NO, NO2, C102 etc.

Answer 2

The diamangnetic materials will not show any ESR spectra.

Explanation:

The electron spin resonance is observed in the compounds having unpaired electron. Electrons have a spin angular momentum as half and for paired electrons, the net spin is zero as the electrons are paired with opposite spin. ESR will not show any signal for the diamagnetic materials where all the electrons are paired with opposite spin.

hence, any diamagnetic material won't have any ESR spectral lines.