# Finding the Partition Function in Paramagnetism

1. Nov 20, 2013

### Ang Han Wei

1. The problem statement, all variables and given/known data

I was given a Hamiltonian H = -$\mu$B$\sum$cos$\alpha_{i}$
where the sum is over i from i = 1 to i = N

I need the partition function given this Hamiltonian.

2. Relevant equations

3. The attempt at a solution

I tried using the classical approach where $Z_{N}$ = $\frac{1}{h^{3}}$$\int$$d^{3}$p$d^{3}$q exp[$\beta$$\mu$B$\sum$cos$\alpha_{i}$], but I am stuck at what to do with the cos summation.

Can anyone help?

Thanks!