Tuning the thorugh bond interaction in a two centre problem

PATRICIA R. LEVSTEIN; HORACIO M. PASTAWSKI; JORGE L. D'AMATO

JOURNAL OF PHYSICS CONDENSED MATTER

IOP

Lugar: London; Año: 1990 vol. 2 p. 1781 - 1794

0953-8984

In  this paper we develop the basis of electron transfer and molecular electronics. We also describe the idea of antiresonance. Two centres A and B connected by one or more sets of bridging states (pathways) define a graph in the space of states. The Hamiltonian is decimated in this space and the problem is reduced to that of two sites with corrected energies E, and E, and an effective interaction VAB. The goal of the method is to make evident how the pathways should be modified in order to tune the resulting coupling. The condition for maximum coupling is i´, = EB (resonance) and is related to a generalised reflection-inversion symmetry while the coupling minimises if VAB = 0 (anti-resonance). This is a non-trivial situation allowed by the topology of the system which occurs when two or more pathways interfere destructively. The effects of resonances and anti-resonances in electron transfer and other applications are discussed. The effects of resonances and anti-resonances in electron transfer and other applications are discussed. B connected by one or more sets of bridging states (pathways) define a graph in the space of states. The Hamiltonian is decimated in this space and the problem is reduced to that of two sites with corrected energies E, and E, and an effective interaction VAB. The goal of the method is to make evident how the pathways should be modified in order to tune the resulting coupling. The condition for maximum coupling is i´, = EB (resonance) and is related to a generalised reflection-inversion symmetry while the coupling minimises if VAB = 0 (anti-resonance). This is a non-trivial situation allowed by the topology of the system which occurs when two or more pathways interfere destructively. The effects of resonances and anti-resonances in electron transfer and other applications are discussed. 2 (1990) 1781-1794(1990) 1781-1794