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The model of the metal bond structure based on an electrostatic coordination sphere as a basic element of the metal crystal lattice is proposed. It is shown that the coordination sphere (CS) is not just a geometric parameter of the atom distribution in a crystal lattice, but a form of joint, cooperative existence of a group of atoms. An electrostatic CS consists of an outer spherical valence electron shell, shell atoms (cations), an inner electron shell and a central atom (anion) of the CS. Due to the multiple mutual overlap of valence orbitals, the valence electrons of each CS atom, both in the outer and inner spherical electron shells, are effected by all atoms simultaneously and, as a result, freely move (exchange) in the field of a single valence orbital. In this case, the behavior of bonding electrons in the CS during their dynamic resonant interaction is indistinguishable from their behavior in a perfect electron gas (Fermi liquid). The main bond between the shell cations and the central anion is ionic. The connection between CS's is carried out electrostatically, during the interaction of orbitals through the CS valence shells with any atom in the volume of the crystal lattice. The entire volume of the metal, like a web, is penetrated by interacting valence spheres of coordination shells. The "electrostatic CS" model shows that the iron polymorphic transformation is a phase transformation based on high-temperature solid-state volume photon ionization. During the ionization process, the CS is stretched and the iron crystal lattice is destroyed with the formation of crystallite nanofragments and amorphization of part of the structure. The proposed model explains the experimental data obtained recently when studying the polymorphism of pure iron under equilibrium conditions. [ABSTRACT FROM AUTHOR]

The traditional method for opening the electron shells of noble gas atoms involves a strong electronegative atom or group. However, this approach is limited to only heavy noble-gas atoms, such as Kr and Xe. In this paper, we performed accurate calculations of He@C8H8 and He@C10H16 and showed the possibility of opening the electron shell of a light noble-gas atom. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In the present paper, we consider mechanical properties of an ideal hexagonal close-packed (HCP) crystal lattice. We construct three models for describing the elastic characteristics of metals with HCP lattice. Using examples of nine metals with different degree of geometric imperfection (beryllium, hafnium, cadmium, cobalt, magnesium, rhenium, titanium, zinc, and zirconium), we show that including the moment interaction into the model leads to a more accurate description of the elastic properties than taking into account the geometric features of a specific lattice. We also show that, depending on the type of the electron shell, it is efficient to use different models; namely, for d-elements, it suffices to use the two-parameter force model, while for the s-elements, it is required to take the moment interaction into account. [ABSTRACT FROM AUTHOR]