been the subject of numerous investigations (Birch, 1960, 1961). In this study, measurement of bulk density and of compressional and rotational wave velocities of a variety of rocks and minerals affords the opportunity of calculating elastic constants and of studying anisotropy in elastic velocities. Although it was not possible to take into account the effect of confining pressure on velocitie...

The effect of fatigue on ZrCuAl amorphous metals induced by mechanical cyclic loading is investigated using inelastic neutron scattering and the pair density function analysis of neutron diffraction data. With cooling, the local atomic structure undergoes reorganization under fatigue that is directly related to the number of fatigue cycles. Also under fatigue, suppression in the atomic dynamics...

Virtually all X-rays imaging in a medical or biological context is performed by measuring differences in the attenuation of X-rays by the tissues. The material properties are inferred from the differences in the number of photons detected at the end of defined paths in the sample. Naturally then this form of X-ray imaging concentrates almost entirely on the particle side of X-ray behaviour. The...

The density-density correlation profiles obtained superimposing absorption images from atomic clouds freely expanding after the release of the confining optical lattice can be theoretically described in terms of a generalized quantum measure based on coherentlike states. We show that the corresponding density patterns differ in a testable way from those computed using standard many-body mean va...

In this paper, we propose a theoretical scheme for the generation of non-classical states of the cavity field in a system of a single trapped atom via controlling the Lamb-Dicke parameter. By exploiting the super-operator method, we obtain an analytical expression for the density operator of the system by which we examine the dynamical behaviors of the atomic population inversion, the phase-spa...

Topological analysis has been performed on the total electron density of the two forms of Ozonemolecule,C2V and D3H ,to investigate the nature of chemical bonds ,molecular structure , atomiccharges and electrical properties. While these concepts have been completely discussed usingclassical models the emphasize in this work is based on Quantum Theory of Atoms in Molecules(QTAIM). Because the D3...

Stabilizations and atomic level quadrupole coupling constant (CQ) properties have been investigated for graphene–like monolayers (G–monolayers) of boron nitride (BN), boron phosphide (BP), aluminum nitride (AlN), and aluminum phosphide (AlP) structures. To this aim, density functional theory (DFT) calculations have been performed to optimize the model structures and also to evaluate the CQ para...

We present results of electronic structure calculations for aluminium contacts of atomic size, based on density functional theory and the local density approximation. Addressing the atomic orbitals at the neck of the nanocontact, we find that the local band structure deviates strongly from bulk fcc aluminium. In particular, hybridization between Al 3s and 3p states is fully suppressed due to di...

Kinetic Monte Carlo simulations on the basis of rates derived from density-functional calculations are used to investigate the atomic processes in molecular beam epitaxy of GaAs. This approach puts us in a position to describe island nucleation and growth in all relevant atomistic detail by bridging the gap in length and time scales between the mesoscopic scale of growth morphology and the atom...

A conceptually new approach is introduced for the decomposition of the molecular energy calculated at the density functional theory level of theory into sum of one- and two-atomic energy components, and is realized in the "fuzzy atoms" framework. (Fuzzy atoms mean that the three-dimensional physical space is divided into atomic regions having no sharp boundaries but exhibiting a continuous tran...