2.Hint 1 The interaction energy of the two dipoles is given by 0={36m,用m.角-㎡6mm} (110) (6,p Use spherical coordinates and take the 2-axis to be the direction of the separation vector.The interaction energy may then be written as Φ mm' R3 {2cos0 cos '-sin 0 sin 0'cos(-)}. (111) The canonical partition function thus takes the following form, z=∫n∫anam() (112) ds =d(cos0)d where is the element of solid angle. Solution 1 Explicitly,we have z=∫∫lsc的ay (113)2. Hint 1 The interaction energy of the two dipoles is given by (110) Use spherical coordinates and take the -axis to be the direction of the separation vector . The interaction energy may then be written as (111) The canonical partition function thus takes the following form, (112) where is the element of solid angle. Solution 1 Explicitly, we have (113)