A Hartree-Fock based (HF), multiconfiguration self-consistent field (MCSCF) method has been used to configure computationally several nonstoichiometric model pyramidal molecules of In, Ga, and As atoms with a predesigned electronic energy level structure. The geometry, structure, and composition of the molecules have been derived from those of the corresponding bulk lattices. Formation of the molecules under conditions mimicking vacuum and quantum confinement has been studied. The results prove that formation conditions affect the molecular parameters (such as the structure and bond length), thus causing significant effects (up to an order of magnitude) on the electronic properties of the molecules, including their charge and spin density distributions (CDDs and SDDs, respectively). The virtual (i.e., fundamental theory based, computational) synthesis of atomic-scale objects with predesigned physicochemical properties is a powerful method that can be used to develop electronic templates of artificial molecules, atomic clusters, small quantum dots (QDs), QD-based nanoheterostructures (NHSs), and other nanosystems of practical interest to guide their experimental realization.

• Received 4 May 2006

DOI:https://doi.org/10.1103/PhysRevB.74.085306