Ab initio electron propagator theory of molecular wires. II. Multiorbital terminal description.
Correlated, ab initio electron propagator methodology may be applied to the calculation of electrical current through a molecular wire. A new theoretical formalism is developed for the calculation of retarded and advanced Green functions in terms of the electron propagator matrix for a bridge molecule. The calculation of the current requires integration in a complex half-plane for a trace that involves terminal and Green function matrices that may have any rank. Because the latter arrays have poles represented by matrices, an alternative expression is developed in terms of ordinary poles which are (n-1)-fold degenerate or nondegenerate. For an arbitrary number of terminal orbitals, the analytical expression for the current is given in terms of pole strengths, poles, and terminal matrix elements of the electron propagator, i.e., the parameters that are found in the output of numerical calculations.
Dahnovsky
Yu
Y
Department of Physics and Astronomy, University of Wyoming, P.O. Box 3905, 1000 East University Avenue, Laramie, Wyoming 82071, USA. yurid@uwyo.edu
Ortiz
J V
JV