Associated Legendre functions and orthogonality

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soikez
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According to the orthogonality property of the associated Legendre function

[tex]P_l^{|m|}(cos\theta)[/tex]

we have that:

[tex]\int_{0}^{\pi}P_{l}^{|m|}(cos\theta){\cdot}P_{l'}^{|m'|}(cos\theta)sin{\theta}d\theta=\frac{2(l+m)!}{(2l+1)(l-m)!}{\delta}_{ll'}[/tex]

What I am looking for is an orthogonality property for the derivative of the associated Legendre function

[tex]P^{'}_{l}^{|m|}(cos\theta)[/tex]:

something like that perhaps:

[tex]\int_{0}^{\pi}P^{'}_{l}^{|m|}(cos\theta){\cdot}P^{'}_{l'}^{|m'|}(cos\theta)sin{\theta}d\theta=?[/tex]

or even taking into consideration the fact that the derivative of the associated Legendre function is:

[tex]P^{'}_{l}^{|m|}(cos\theta)=\frac{lcos{\theta}P_{l}^{|m|}(cos\theta)-(l+m)P_{l-1}^{|m|}(cos\theta)}{sin\theta}[/tex]

after some manipulations on my equation an orthogonality property over the sum below:

[tex]\sum_{l}^{\infty}\sum_{m=-l}^{m=l}cos{\theta}P_{l}^{|m|}(cos\theta)-(l+m)P_{l-1}^{|m|}(cos\theta)e^{jm\phi}[/tex]

Thanks in advance
 
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I am looking for a similar thing. I have looked in all the spherical harmonics textbooks I can find, but have had no luck. I will let you know if I have anything.