In this diploma thesis, Monte Carlo (MC) simulations for an ionic system between two parallel uniformly and discretely charged plates were performed. This model system is an approximation which enables the study of interactions between same charged particles. The simulations were used to illustrate the differences that occur when discrete charge is introduced in place of a uniform charge. It was our aim to also test how different patterns of discrete charge influence the force. With discrete charge, counterions concentrate more towards the charged walls inducing a weaker repulsive force compared to the one observed for uniform charge. Calculations of pressure, based on the contact concentrations of counterions, however, predicted an even stronger repulsion. We must therefore conclude that for discretely charged particles this approach is unsuitable for the prediction of particle interactions. At suitable conditions, however, the same method was successful in predicting an effective attractive force for uniformly charged particles. When compared, smaller dispersed discrete charge (resembling the uniform charge) produced a strong similarity for both pressure and the concentration profiles to that of the uniform charge. We found no significant difference between the different discrete patterns of charge.
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