Holes interaction

Brus L E 1984 Electron-electron and electron-hole Interactions In small semiconductor crystallites the size dependence of the lowest excited electronic state J. Chem. Phys. 80 4403-9... 

Brus, L. E. (1984). Electron-electron and Electron-Hole Interactions in Small Semiconductor... 

The above observation suggests an intriguing relationship between a bulk property of infinite nuclear matter and a surface property of finite systems. Here we want to point out that this correlation can be understood naturally in terms of the Landau-Migdal approach. To this end we consider a simple mean-field model (see, e.g., ref.[16]) with the Hamiltonian consisting of the single-particle mean field part Hq and the residual particle-hole interaction Hph-... 

In the Landau-Migdal approach the effective isovector particle-hole interaction Hph is given by... 

If we neglect the electron-hole interaction, as in Chapter 1, then a metal-insulator transition should occur when the two bands overlap. For infinite values of a, the separation in energy between the two bands should be just the Hubbard Uy so the transition occurs when... 

Coiled-coil helices usually have one stripe of residues engaged in knobs-into-holes interactions. There are, however, instances where a helix may engage in such interactions along two stripes (Cohen and Parry, 1990 Walshaw and Woolfson, 2003 Walshaw et ah, 2001). For example, helices of four-stranded coiled coils make their primary knobs-into-holes contacts... 

Fig. 5. Schematic diagram of complementary binding sites or knob-hole interactions in fibrin polymerization. Fibrinopeptides in the central domain cover knobs that are complementary to holes that are always exposed at the ends of the protein. When the fibrinopeptides are removed by thrombin, knob-hole interactions occur, giving rise to the two-stranded protofibril made up of half-staggered molecules.

The presence in the cluster of a positively charged impurity has also been considered, analyzing, by first principles, the screening due to the Si-NCs [123,124]. A reduction of screening in Si nanostructures with respect to bulk Si has been already observed [52] and predicted [125]. This reduction is a fundamental process at the basis of the enhancement of both the electron-hole interaction and the impurity activation energies in nanosized objects, and is due to the fact that close to the surface there is a dielectric dead layer, with a finite-range reduction of the dielectric constant due to the dielectric mismatch at the nanocrystal-environment interface. 

In particular we will show the dependence of the electronic gap on both wire size and orientation. Further, in some of the studied wires, self-energy corrections, by means of the GW method, and also electron-hole interaction, by solving the Bethe-Salpeter equation, will be included in order to have an appropriate description of the excited states. 

The relativistic or non-relativistic random-phase approximation (RRPA or RPA)t is a generalized self-consistent field procedure which may be derived making the Dirac/Hartree-Fock equations time-dependent. Therefore, the approach is often called time-dependent Dirac/Hartree-Fock. The name random phase comes from the original application of this method to very large systems where it was argued that terms due to interactions between many alternative pairs of excited particles, so-called two-particle-two-hole interactions ((2p-2h) see below) tend to... 

Marko Hrovat, Ariane Ahmad-Khanlou, Zoran Samadzija, Janez Hole, Interactions between lanthanum gallate based solid electrolyte and ceria , Materials Research Bulletin, 34[12/13], 2027-2034 (1999). 

---