Hole motion

Density of states weighted Franck-Condon factor Deoxyribonucleic acid Barrier height for the adiabatic hole motion Difference in ionization potentials of adenine-thymine and guanine-cytosine base pairs... 

We consider first the case where Hq corresponds to free hole motion, given by Eq. 2 with o =0 and also A=0 because we are discussing only static solutions here. In all that follows we restrict ourselves to the case where the DNA stack consists of the same base pair repeated, which means that d in Eq. 2 may also be taken equal to zero. 

Fig. 6.124. Since hole motion is in a direction opposite to electron motion, a hole behaves as if it were positively charged.

A long-range or even a mesoscopic AFM order (Neel ordered) encumbers the hole motion. (As a hole moves to the nearest-neighbouring site, the spin at that site concomitantly moves to the site previously occupied by the hole). A succession of such moves shift-registers a line of spins, which become laterally misaligned with respect to the spins on the sides (Figure 4). The broken AFM bonds shown by the dashed lines create a linearly rising potential that impedes free hole motion. A compact... 

In our lattice model, each lattice site occupies a single lattice cell of volume v. In view of the cooperative nature of the hole motion, the barrier energy is treated by a mean field average [28], and is related to the Gibbs free energy per molecule (Ag) in a system restrained to single occupancy of cells by... 

Fig. 3. Calculated equilibrium and nonequilibrium volumes of PVAc as a function of temperature and cooling rate [28]. Circles are experimental data [29]. The lattice thermal expansion coefficient (a ) is related to the occupied volume and has nothing to do with Tg. The kinetics of the glass transition is determined by the dynamics of hole motion...

The fractal dynamics of holes are diffusive, and the diffusivity depends strongly on the tenuous structure in fractal lattices. The fractal dimension defines the self-similar connectivity of hole motions, the relaxation spectrum, and stretched exponential... 

Suppose some people are sitting in a row at a movie theater, with a single empty seat on the left end of the row. Every 5 minutes, a person moves into a seat on his or her left if it is empty. In what direction and with what speed does the empty seat move along the row Comment on the connection with hole motion in p-type semiconductors. 

Figure 12-26. Time-of-light signals for hole motion in DPOP-PPV at different temperatures and electric fields. The sample thickness was 4 pm Arrows indicate the transit time (Ref. [83]).

In the silver halides Mott and Gurney suggested a mechanism for the formation of colloidal Ag [167]. A conduction-band electron produced by irradiation is first trapped at a lattice imperfection which may be a silver atom or ion, a chemical impurity, or a trapping site along a dislocation. The trapped electron then attracts a Ag interstitial ion to form a Ag atom. Following this, electrons and Ag " interstitials are trapped at the site in proper sequence to cause the buildup of a colloidal silver particle. This mechanism requires the presence and mobility of silver ions, and it is further required that the hole motion be sufficiently small that trapped electrons are not annihilated by electron-hole recombinations. 

The strong-confinement regime corresponds to the opposite limit, d < 2<2q. In that case the relative electron-hole motion is strongly affected by the barriers. In the direction of restricted motion, the kinetic energies of the lowest-energy electron and hole states determined by the quantum confinement are larger than the Coulomb... 

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