  Our previous work show that in the molecular cluster regime, the band blue
shift associated with cluster growth can be understood by a model that assume
electrons are confined to a spherical potential well and the clusters are made
of some basic units. A formula is given for the lowest excited electronic state
energy. This expression contains an electron-hole-pair (EHP) delocalization
constant as an adjustable parameter which, however, can be anchored to a
definite value through the known transition energy at the spectra turn-around
point. We also proposed symmetry and probability principles in molecular
cluster growth range to explain the molecular cluster electron absorption
spectra turn-around phenomena and unusual isotopic properties of small silver
bromide clusters. In this paper, based on systematical review of Quasi-Elastic
Light Scattering (QELS), Fourier-transform infrared spectroscopy (FTIR) and
Direct Laser Desorption Mass Spectra (DLD-MS) experiments of silver bromide
clusters prepared via the electroporation of vesicles, we show how the symmetry
and probability principles in molecular cluster growth range can be used to
explain the lager silver bromide molecular cluster formation in a bilayer
formation mechanism. The turn round curve of energy gap vs confine sphere size
had been proved to be a right curve to describe the molecular cluster quantum
confinement behavior. We also defined Electron Delocalized Status (EDS),
Electron Localized Status (ELS), and EDS/ELS switch or quantum confinement
switch (QCS) in the quantum confine system. These studies pave the theoretical
and technical ways for advanced device technology continue shrink and new
concept device generation in the atomic and molecular cluster size range.

Chemical Physics