In this method, use is made of the Zeeman interaction of the magnetic dipoles associated with the nucleus of the electron, when placed in an external magnetic field. Accordingly, they are identified as NMR (Nuclear Magnetic Resonance) or ESR (Electron Spin Resonance). This form of spectroscopy finds many applications in many diverse branches of Physics, Chemistry and Biology.
This set-up is designed, keeping in mind the basic objectives of a classroom experiment. The observation of ESR in low magnetic field and in a radio frequency makes this apparatus very simple, inexpensive and within reach of every Post Graduate laboratory.