In the meanwhile, what makes the differentiation of rentier models more serious than other models is the change in the content and function of the convergence of individuals in the form of common interests that lead to the formation of interest groups. Therefore, based on the political economics framework and in order to adapt the performance of actors in the field of power and wealth in Rentier models, this research has tried, based on the role of the interest groups, to analyze the paradox of democracy and the rent and provide a conceptual model corresponding with realities. Due to the lack of statistical data in relation to the interest groups in Rentier models, it was imperative that the problem-solving approach in this research be based on the library resources and the theoretical analysis based on the deductive method, so that within the framework of the quantum paradigm can be achieved the overall vision and design of the desired logical model. The results of this research are aimed at a new explanation of the functioning of interest groups in Rentier models, which this is a ground for the creation of an index called the rate of convertibility of power-wealth, in order to provide a comprehensive and exclusive definition of a rentier state. The use of this index has shown that since the development of democracy leads to an increase in the penetration of interest groups, in the rentier models the development of democracy will increase the instability of the economic structure.
