Änderung der Elektronendichte im H-Atom bei strahlungsinduzierten Übergängen (computergraphische Rasterdarstellungen). Die Wellenfunktion des H-Elektrons ist numerisch in zeitabhängiger Störungstheorie mit Dipolnäherung berechnet. Übergang 1s [-] 2p (m = 0,±1): lineare Oszillation der Elektronendichte (XZ-Ebene; lineare Polarisation); Übergang 1s [-] 2p (m = 1): rotatorische Ladungsbewegung (XY-Ebene; zirkulare Polarisation).

Radiative transitions of the hydrogen atom are discussed on the basis of the semi-classical model. Here the radiation is described by classical electrodynamics whereas the H atom is treated quantum mechanically. The coupling between the atom and the radiation field is accounted for by time dependent perturbation theory. After a brief discussion of the theoretical basis of the semi-classical model the radiative transitions 1s [-] 2p (m = 0,±1) are described in some detail. In particular, results are given for the time dependence of the center of gravity [r ] of the electron density and of the density itself. Also, comparison of the rotating wave approximation with the exact numerical solution of the semi-classical model is made. This manuscript forms a theoretical basis of the film which shows the time dependence of the electron density for the above transitions using an animation based on computer graphics.