Question

For a paramagnet that obeys the Curie-Weiss law, show that: a. The effective number of Bohr magnetons per molecule is given by ef 2.83 CM, where CM is the Curie constant per molecule h. The molecular field is given by OH H.

Answer 1

Quantum Theory of Para magnetism According to this Magnetic moment parallel to H = M_J g mu_B H Potential energy = -M_J g mu_B H. According to Maxwell Boltzmann's law th eponic susceptibility is X = 1/H sigma^J_m = -J M_J g mu_B e^M_J g mu_B/KT)/sigma^J_m = -J E^(M_J g mu_B^h/KT) straightline (A) Because In gas, no of atoms with Particular value of H will be proportional to exp (M_J g mu_B H/KT) If M_J g mu_B H < < KT & e^x = 1 + x + --- The exp (M_J g mu_B H/KT) = [1 + M_J g mu_B H/KT] \r\n Hence eqn (A) will be X = 1/H g mu_B M sigma^J_M_J = -J M_J + g^2 mu B^2 H K.T sigma^J_M_J = -J <_J^/sigma^J_M_J = -J + g_mu B/KT sigma^J_M_J = -J M_J Because sigma^J_M_J = -J M_J = & sigma^J_M_J = -J = (25 + 1) & sigma^J_M_J = -J M_J^2 = J(J +