CHARGE-TRANSFER BETWEEN A MOLECULE AND AN INFINITE ELECTRON RESERVOIRIN THE MO SCHEME

A quantitative reference for comparing molecules (and sites of molecul es) Likely to exchange electrons with a molecular or crystalline partn er can be obtained by coupling such molecules to a model electron rese rvoir with a continuous energy spectrum. In this study the required pr ocedure is defined and mathematically formulated, within the standard orbital scheme. The reservoir is modeled as an infinite linear chain o f atoms with one atomic orbital whose coupling is larger than the larg est half-bandwidth of the molecules to be compared, coupled by a suita ble bond parameter to a specific site of the molecule. The resulting l evel broadening and local density of states (DOS) are determined using Dyson's equation to get a tractable expansion of the Green function o f the molecule-reservoir system. An example of application and a brief discussion of the dependence of the results on the type of Hamiltonia n utilized are given. (C) 1996 John Wiley & Sons, Inc.