The subscripts of C and V are the conduction band and
valence band, respectively.
At normal pressure, the single
valence band, which is positioned at the bottom of the
valence band arise from 2[s.sup.2] electrons of O.
The reaction is initiated by the excitation of
valence band electrons and photo injection of photocatalyst in presence UV light [10].
V is the matrix element describing the coupling between the host
valence band and the Bi related impurity level and [C.sub.Bi] is the coupling parameter which is used as a fitting parameter in our model [10].
In the amorphous semiconductor materials, the optical transition is from the valence-band tail states to the conduction band and from the extended states in the
valence band to the conduction-band tail states (14).
[8] showed that the AIK[beta] emission (3p-1s transition) from alumina crystals is accompanied by a small high energy weak emission peak located 0.6 eV above the top of the
valence band.
The position of conduction and
valence bands of CdS and CdSe are recorded in Table 1.
In the presence of a magnetic field parallel to the z direction, the energies of electrons and holes in the conduction bands and
valence bands are as follows:
In AlN, the metallization occurs through indirect closing of the band gap between
valence band maximum at [GAMMA] point and conduction band minimum at X point.
W[O.sub.3] film exhibits a broad range of functional properties, such as small band gap energy (2.4-2.8eV), deeper
valence band (+3.1 eV), stable physicochemical properties, and strong photocorrosion stability in aqueous solution [410].