Model clusters (NH3)(4)(+2) and (NH3-H2NO.)(4)(+2) are introduced as simple models for a pure organic conductor. Then theoretical calculations of the total energies of ab initio solutions, in which the spin or charge density are arranged alternately, and intermolecular magnetic interactions are carried out by ab initio MO-DFT method. The result shows that these model clusters are efficient for ab initio investigation of the electronic properties of organomagnetic conductors.