Modellierung der Nahordnung von amorphen Systemen mit Computersimulationen Three different amorphous systems have been modelled with the computer simulation methods Monte Carlo (MC) and Reverse Monte Carlo (RMC) in order to determine the intermolecular structure and intermolecular pair potentials. The simulations are based on the total atom pair correlation functions that have been determined by X ray (fluid CF4 fluid ethane) and neutron diffraction (molten ZnCl2) experiments at different temperatures and densities. The experimental functions of fluid CF4 have been reproduced in MC simulations with a simple five center Lennard Jones potential. The molecules are statistically distributed and no preferred intermolecular orientation is visible. In addition the agreement with the RMC results is good. The MC simulations on fluid ethane were performed with an empirically determined modified eight center Lennard Jones potential. The molecules are also statistically distributed. Furthermore the angle dependend correlation functions for four special orientations between two neighboured molecules (crossed T shaped parallel adjacent and parallel end to end) show that no preferred orientation exists. The RMC simulations confirm these results. For the MC simulations of molten ZnCl2 a special pair potential was developed that simulates the polarisation effects with a damped Coulomb function in combination with an oscillating function for the Zn Zn interaction. This potential generates density fluctuations in the Zn substructure that give rise to the prepeak. The melt consists of ZnCl4 tetrahedra of high regularity that are connected together via Cl bridges and form a threedimensional network. For this system the MC method has turned to be more reliable than the RMC method.