Superexchange coupling and electron transfers in large three-dimensional disordered media

✍ Scribed by J.-M. Lopez-Castillo; A. Filali-Mouhim; I.L. Plante; J.-P. Jay-Gerin

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 480 KB
• Volume: 239
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)00459-h

✦ Synopsis

The superexchange coupling (V~) in large three-dimensional electron-transfer systems is an intricate function of a huge number of variables suggesting the possibility for a self-averaged and universal behavior. By studying a wide class of disordered model systems presenting through-space interactions, we find that self-averaging does occur in narrow-band systems. V~ is then characterized by a unique control parameter (E/I"), the ratio of the energy gap to the half-bandwidth of the medium. The sign of E/1-', distinguishing electron-from hole-transfer processes, is a major determining factor of the behavior of Vs.