Magnetic Field Induced Absorption:

The elementary particles like as electrons and nucleons are associated along with magnetic properties. While subjected to external strong magnetic field, the interactions among the internal and external magnetic fields provides rise to additional quantised energy levels. The difference in the energies of these levels is small and transitions are brought about through absorption of the radiation of longer wavelength ranges. The transitions amongst the energy levels produced because of the interaction of the nuclear magnetic moment along with the applied magnetic field are studied using radio-waves within the range of 30 to 500 MHz and give rise to Nuclear Magnetic Resonance (NMR) spectroscopy. The energy separation of the stages created by interaction among the electron magnetic moment along with the applied external field is even smaller. These are studied under Electron Spin Resonance (ESR) Spectroscopy through using microwaves of a frequency of about 9500 MHz.

You might be wondering in which what happens to the absorbing species after it has absorbed the photon. Where does this extra energy go? Does it bring within some kind of a change in the structure of the species? Instead, what is the fate of the absorbed radiation?