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[en] The crystal structure data of Sr₅Si₃ are given including the XRD data, atomic coordinates and thermal displacement parameters

No abstract available

[en] A new class of beryllium-boron clusters, beryllo-borospherene, is described herein theoretically. When beryllium is gradually added to the B${}_{12}$ motif, it undergoes drastic structural modifications. The global minimum of the Be${}_4$B${}_{12}$${}^{+}$ cluster is an Archimedean beryllo-borospherene in a ${}^2$A${}_1$ electronic ground state, composed of four boron triangles linked at each corner, resulting in a truncated tetrahedron with four B${}_6$ rings capped with four beryllium atoms. Beryllium forms strong bonding with the boron clusters through strong electrostatic and covalent interactions. For instance, the bonding between a beryllium atom and Be${}_3$B${}_{12}$ unit is best described as a Be${}^{+}$ fragment in a ${}^2$P excited state forming a strong and polarized electron-sharing bond with Be${}_3$B${}_{12}$, followed by several dative interactions by employing its vacant s, p, and very high-lying d orbitals. Counterintuitively, for an s-block element, the p orbitals of beryllium are the most crucial atomic orbitals for bonding rather than s orbitals. (© 2022 Wiley‐VCH GmbH)

[en] The crystal structure data of Sr₅Ge₃ are given including the XRD data, atomic coordinates and thermal displacement parameters

[en] Full text.Based on a pseudopotential scheme, the composition dependence of energy band-gaps of zinc-blende Mg_xZn_1-xSe ternary alloys in the composition range of ≤ x ≤ 1 are determined. The effect of deviation of lattice constants of the alloys of interest from Vegard's law on the optical bowing parameter and system transition between the direct and indirect structures is discussed

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[en] Parameters of the electric field gradient tensors have been found for the Cu and Ba sites of the Tl₂Ba₂Ca_n-1Cu_nO_2n+4 lattices by the ⁶¹Cu(⁶¹Ni), ⁶⁷Cu(⁶⁷Zn) and ¹³³Ba(¹³³Cs) emission Moessbauer spectroscopy. The same parameters have been calculated using the point charge approximation. An analysis of the obtained quantities has been carried out taking into consideration literature data on the ⁶³Cu nuclear quadrupole resonance. Agreement of the measured and calculated parameters could be reached assuming the holes resulting from lowering the valence of part of the Tl atoms to be placed mainly at oxygen sites of the Cu-O planes (especially, at oxygen sites of the Cu(2)-O planes for the Tl₂Ba₂Ca₂Cu₃O₁₀ compound). (orig.)

[en] Composition of lamprophyllite of the Kola peninsula was analyzed and crystal structure was specified. It was established that Na and Ca were contained in the interpacket space. 11 refs., 1 fig., 2 tabs