Lattice properties

Conventional physical descriptions of materials in the solid state are concerned with solids in which properties are controlled or substantially influenced by the crystal lattice. When defects are treated in typical solid state studies, they are considered to modify and cause local perturbations to bonding controlled by lattice properties. In these cases, defect concentrations are typically low and usually characterized as either point, linear, or higher-order defects, which are seldom encountered together. 

This paper presents the results of ab initio calculation investigating the pressure dependence of properties of rutile, anatase and brookite, as well as of columbite and hypothetical fluorite phases. The main emphasis is on lattice properties since it was possible to locate transitions and investigate transformation precursors by using constant-pressure optimization algorithm. 

O. Fischer and M.B. Maple, Eds., "Superconductivity in Ternary Compounds I, Structural, Electronic and Lattice Properties , Springer-Yerlag, New York (1982). 

We may now consider the most basic form of the relationship between lattice properties and one of the most important physical properties of the bismuthates, the superconducting Tc, as derived from the theories of Bardeen, Cooper and Schrieffer ... 

This chapter reviews the properties of ferromagnetic III-Vs, and is organized in the following way. Section 2 describes the preparation of ferromagnetic III-Vs, and is followed by the presentation of lattice properties in section 3. In section 4, spin and charge states of... 

What is as noteworthy as the excess of 88a from the solid-state irradiation of 86a is the presence of any 87a at all. Its formation requires either that one of the more distant -/-hydrogen atoms be abstracted also or that the reaction cavity suffer some dramatic changes in shape and size while the hydroxy-1,4-biradical is present. Based upon the lattice properties of 86a, the latter seems the more probable scenario without the movement of groups on adjacent... 

We shall consider, in detail, studies of MgO lattice properties using the potential-induced breathing model and three complementary band-theoretical studies of electron distribution. Early studies using the modified electron-gas method (Cohen and Gordon, 1976) gave reasonably good agreement with experiment for equilibrium static lattice properties and... 

Because the diffraction pattern of a crystal is the periodic superposition (or product, or convolution) of the continuous transform of the unit cell contents with the lattice transform, other interesting consequences follow. For example, the locations of reflections in the diffraction pattern of a crystal, the net or lattice on which they fall, is entirely determined by the lattice properties of the crystal, namely the unit cell vectors. They in no way depend on the structure or properties of the molecules that fill the unit cells. On the other hand, the intensity we measure at each point in the diffraction pattern, and its associated phase, is entirely determined by the distribution of electrons, the positions of atoms xj, yj, Zj, within the unit cells. 

Fischer, O. Maple, M. B., Eds. Topics in Current Physics, Vol, 32 Superconductivity in Ternary Compounds I Structural, Electronic, and Lattice Properties Springer-verlag, New York, 1982. 

At the next step (k 1,2,..., ), each bond of the lattice was replaced by a lattice generated at the previous step (Fig. 12) The eventual independence of the lattice properties from the iteration number n was recognized as the termination of the iteration process. Lattices with linear dimensions / (assumed to exceed by far the correlation length) generated in this way were used to calculate the effective physical properties. It is clear that the ensemble of bonds po)... 

The EMA rests on the assumption that if the QD is larger than the lattice constants of the crystal stmctnre, then it will retain the lattice properties of the infinite crystal and the same valnes of the carrier effective masses the electronic properties of the... 

Dresselhaus, G. (1984). Electronic and lattice properties of graphite. Proceedings of the Workshop on the Electrochemistry of Carbon. Pennington The Electrochemical Society, p. 5. 

In the present discussion, attention is focused on the properties of the electron gas at the surface of the metallic crystal. As far as the metal atoms are concerned the lattice terminates sharply at the surface, which is called the jellium edge in this model. The important feature of the electron cloud is that it spills out over the edge of the lattice to an extent which is determined by lattice properties such as and d, and by electron gas properties such as N ). When the jellium model is... 

The silver halides, with the exception of one crystal modification of Agl, have cubic crystal structures. Crystal structure data, relevant lattice properties and low temperature dielectric constants, are collected in Table 3. AgF, AgCl, and AgBr all have the NaCl rocksalt structure in which there are four silver halide pairs per nonprimitive unit cell with cation-anion nearest neighbor distances equal to one-half a lattice constant. 

Empirical fitting is essentially the reverse of the lattice simulation methods discussed in Section 4, in that structural and lattice properties are used to determine the potential, by requiring that the potential reproduces these properties. 

In an interesting study, Hase et al. (189) looked at the effect of the lattice properties of a (111) diamond surface on the association of a gas-phase H atom with that surface. The authors emphasize the importance of ZPE in the lattice in a full understanding of the dynamics. 

In the case of QW heterostructures, the electron and hole of an exciton are well confined within the layer since the band gap discontinuity is quite large, especially for III-V heterostructuies. On the other hand, dielectric and lattice properties of group III (II) and group V (VI) semiconductors (dielectric permittivities, lattice constants, elastic moduli) are in close proximity in their values [7]. Therefore, we model our system by the localized quasi-2D IS-exciton interacting with bulk-like phonon modes in the QW with infinite potential barriers. We describe such an excitonic state by quasi-2D wave fimction... 

Typical lattice structures used for percolation theory. For percolation lattices, like the square lattices shown here, there is a qualitative difference between lattice properties at low and high porosities. When the lattice has a low porosity, such as the 20% filled square lattice... 

There are, of course, other reasons why radiation-induced decomposition of azides is of interest. Some of the azides have technological applications related to their chemical or explosive instability. This instability, as discussed in other chapters, is clearly related to the electronic and lattice properties of the materials. It has been pointed out that there is a possible relationship between stability and electronic structure [1], and others have indicated the possible role of... 

---