Rehybridization of electronic structure in compressed two-dimensional quantum dot superlattices

Two-dimensional superlattices of organically passivated 2.6-nm silver quant um dots were prepared as Langmuir monolayers and transferred to highly orie nted pyrolytic graphite substrates. The structural and electronic propertie s of the films were probed with variable temperature scanning tunneling mic roscopy. Particles passivated with decanethiol (interparticle separation di stance of similar to 1.1 +/- 0.2 nn) exhibited Coulomb blockade and stairca se. For particles passivated with hexanethiol or pentanethiol (interparticl e separation distance of similar to 0.5 +/- 0.2 nm), the single-electron ch arging was quenched, and the redistribution of the density of states reveal ed that strong quantum mechanical exchange, i.e., wave-function hybridizati on, existed among the particles in these films. [S0163-1829(99)03604-8].