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4.5 Legendre'sche Polynome

Eigenfunktionen des Drehimpulsoperators $ \vec{L}^{2}_{}$ und $ \vec{L_z}\,$ in der Quantenmechanik 4.4

fn(x) = Pn(x) mit 0 $\displaystyle \leq$ n $\displaystyle \leq$ $\displaystyle \infty$, Nn2 = n + $\displaystyle {1 \over 2}$, a = - 1b = 1, w(x) = 1 (4.26)

P0(x) = 1        P1(x) = x        P2(x) = $\displaystyle {1 \over 2}$(3x2 - 1)        P3(x) = $\displaystyle {1 \over 2}$(5x3 - 3x) (4.27)

allgemein:

Pn(x) = $\displaystyle {1 \over {2^n n!}}$$\displaystyle {d^n \over {dx^n}}$(x2 - 1)n (4.28)

P2n + 1(0) = 0        P2n(0) = (- 1)n$\displaystyle {{(2n)!}\over{2^{2n}(n!)^2}}$        Pn($\displaystyle \pm$1) = ($\displaystyle \pm$1)n (4.29)

Rekursionsformel:

(n + 1)Pn + 1(x) = (2n + 1)xPn(x) - nPn - 1(x) (4.30)

((1 - x2)$\displaystyle {d^2 \over {dx^2}}$ - 2x$\displaystyle {d \over {dx}}$ + n(n + 1))Pn(x) = 0 (4.31)

(1 - x2)Pn'(x) = n(Pn - 1(x) - xPn(x)) = $\displaystyle {{n(n+1)} \over
{2n+1}}$(Pn - 1(x) - Pn + 1(x)) (4.32)

Pl(cos($\displaystyle \theta$)) = $\displaystyle {4\pi \over {2 l + 1}}$$\displaystyle \sum_{m=-l}^{l}$$\displaystyle \overline{Y_l^m(\theta_1, \phi_1)}$Ylm($\displaystyle \theta_{2}^{}$,$\displaystyle \phi_{2}^{}$) (4.33)

$\displaystyle {1 \over {\vert\vec{r_1}-\vec{r_2}\vert}}$ = $\displaystyle {1 \over \sqrt{r_1^2+r_2^2+2 r_1 r_2 \cos(\gamma)}}$ = $\displaystyle \sum_{l=0}^{\infty}$$\displaystyle {r_<^l \over r_>^{l+1}}$Pl(cos($\displaystyle \gamma$)) (4.34)


next up previous contents
Next: 4.6 Kugelflächenfunktionen (Spherical harmonics) Up: 4. Orthogonale Funktionensysteme Previous: 4.4 Sphärische Besselfunktionen   Inhalt
Alexander Wagner
2000-04-14