Langevins Theory For Diamagnetic Material

Langevin’s theory for diamagnetic material: Consider an electron (mass =m, charge = e) rotating about the nucleus (charge=Ze) in acircular orbital of radius r. let ω₀be angular velocity of electron. Then

Let a magnetic field of induction B be now applied.B is normal to and into the page

Thus the angular frequency is now different from The result of establishing a field of flux density B is to set up a processional motion of the electronic orbits with angular velocity  eB/-m this is called the Larmor theorem. Then