Differential equation similar to Legendre

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Physicslad78
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I am trying to solve the following differential equation:

[tex] (\frac{L^2}{6k^2}+\frac{w\sqrt{3}}{2}\sin^2\theta\cos 2\phi)\psi=E\psi[/tex]

where [tex]L^2[/tex]is the angular momentum given by:
[tex]\frac{1}{\sin\theta}\frac{\partial}{\partial\theta}(sin\theta\frac{partial}{\partial\theta})-\frac{1]{sin^2\theta}\frac{\partial^2}{\partial\phi^2}[/tex]. [tex]\theta[/tex] goes from 0 to [tex]\pi[/tex] while [tex]\phi[/tex] goes from 0 to 2 [tex]\pi[/tex]. [tex]k[/tex] and [tex]w[/tex] are constants and E is the energy of the system.. This differential equation seems non separable. Any ideas how to solve it...I also realized that the term [tex]sin^2\theta\cos 2\phi[/tex] is a combination of [tex](Y_{2,-2]+ Y_{2,2})[/tex]. But then how to continue?

Thanks
 
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Sorry L^2 is:
[tex] \frac{1}{\sin\theta}\frac{\partial}{\partial\theta} (\sin\theta\frac{partial}{\partial\theta})-\frac{1]{\sin^2\theta}\frac{\partial^2}{\partial\phi^2}<br /> [/tex]
 
You mean

[tex]L^2 = \frac{1}{\sin\theta}\frac{\partial}{\partial\theta}\left(\sin\theta\frac{\partial}{\partial\theta}\right)-\frac{1}{\sin^2\theta}\frac{\partial^2}{\partial\phi^2}.[/tex]

Some ideas: apply the operator to [itex]Y_L^M[/itex] with arbitary values of [itex]L,\,M[/itex] and see if you can determine [itex]L,\,M[/itex] using the properties of the polynomials, or maybe using a linear combination of Legendre polynomials, or appliyng the operator to [itex]f(\theta)Y_L^M,\,g(\phi)Y_L^M,\,h(\theta,\phi)Y_L^M[/itex] and use the properties of the polynomials to simplify the equation and determine [itex]f,\,g,\,h[/itex].

Just ideas.
 
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