Zur Spinpolarisation langsamer Elektronen nach der Streuung an Molekülen

Cross sections and spin polarization of low-energy electrons scattered by I₂ and C₂H₅I molecules were measured in the energy range from 200 to 600 eV and angular range from 30 to 150°. At the same time, several authors made calculations of cross sections and polarizations based on the following assumptions: The molecule consists of free atoms which are independent of each other (the influence of binding is negligible) and scattering of an electron does not occur more than once within the molecule. The agreement between theory and experiment in a wide angular range justifies these assumptions for the present problems. Polarization values lower than the theoretical ones were measured only at scattering angles where the theory predicts very narrow and high values of the spin polarization. Qualitative arguments show that intramolecular scattering very likely is responsible for the deviations found between theoretical and experimental polarization peaks. By means of the polarization of the scattered intensity one can easily decide how much of the scattered intensity comes from one part of the molecule and how much comes from the other part.