Although fill allocation methods to enable reduced metal height variations and manually applicable design guidelines to reduce coupling capacitances are available, the synthesis of fills according to these allocations or guidelines is not well automated. Current fill insertion algorithms mostly use simple mask operations, which fail to enable the implementation of complex design guidelines. The proposed fill synthesis model not only enables implementation of such guidelines, but is also suitable for insertion of standard fill patterns. The proposed novel model has an intricate analogy to the electrons filling the orbits of an atom. Through the proposed method, the task of designing an optimal fill configuration is carried to the CAD tool designer in terms of designing a suitable energy network or rules, albeit in an easier way through provided insights and models.