Expansion in spherical harmonics sin(theta)

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Gerenuk
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Homework Statement



I want to expand sin(theta) in spherical harmonics.
Well, actually I want
(3cos^2(theta+45°)-1)*exp(i*(psi+45°))
but I think I could find my mistake by the above simple example.

Homework Equations



http://en.wikipedia.org/wiki/Spherical_harmonics

The Attempt at a Solution



I seem to get zero for all coefficients by the integrals from wikipedia.
Can I not expand along an arbitrary axis?
 
on Phys.org
The coefficients are not all zero. For instance, the first coefficient is proportional to:

[tex]f_{0}^0 \alpha \int^{2\pi}_{0}d\phi\int^{\pi}_{0}d\theta sin^{2}(\theta)=\pi^2[/tex]