Possible non-centrosymmetric structure of vaterite type yttrium orthoborate
نویسندگان
چکیده
منابع مشابه
Centrosymmetric and pseudo-centrosymmetric structures refined as non-centrosymmetric.
The behaviour of the Flack parameter for centrosymmetric and pseudo-centrosymmetric crystal structures based on crystal structures published as being non-centrosymmetric is presented. It is confirmed for centrosymmetric structures that the value obtained for the Flack parameter is critically dependent on the Friedel coverage of the intensity data, approaching 0.5 for a coverage of 100% and stic...
متن کاملRedetermination of Nd2Ti2O7: a non-centrosymmetric structure with perovskite-type slabs
Single crystals of dineodymium(III) dititanium(IV) hepta-oxide, Nd2Ti2O7, were synthesized by the flux method and found to belong to the family of compounds with perovskite-type structural motifs. The asymmetric unit contains four Nd, four Ti and 14 O-atom sites. The perovskite-type slabs are stacked parallel to (010) with a thickness corresponding to four corner-sharing TiO6 octa-hedra. The Nd...
متن کاملLi13.7Rh8Si18.3 – A Non-Centrosymmetric Variant of the R-Phase Structure
The silicide Li13.7Rh8Si18.3 was synthesized from the elements in a sealed niobium ampoule at 1370 K followed by slow cooling. The sample was studied by powder and single-crystal X-ray diffraction. Li13.7Rh8Si18.3 crystallizes with a non-centrosymmetric occupancy variant of the R-phase structureMg32(Al, Zn)49: I23, a = 1306.9(2) pm,wR2 = 0.0447, 1286 F2 values, and 53 variables. Striking struct...
متن کاملCrystal structure of non-centrosymmetric bis(4-methoxybenzylammonium) tetrachloridozincate
The structure of the title non-centrosymmetric organic-inorganic hybrid salt, (C8H12NO)2[ZnCl4], consists of two 4-meth-oxy-benzyl-ammonium cations sandwiched between anionic layers, formed by isolated tetra-chlorido-zincate tetra-hedra. The double layers extend parallel to the ac plane. The crystal packing is assured by Coulombic inter-actions and by a complex N-H⋯Cl and C-H⋯Cl hydrogen-bondin...
متن کاملNon-centrosymmetric Na3Nb4As3O19
A new non-centrosymmetric compound, tris-odium tetra-niobium triarsenic nona-deca-oxide, Na(3)Nb(4)As(3)O(19), has been synthesized by a solid-state reaction at 1123 K. The structure consists of AsO(4) tetra-hedra and NbO(6) octa-hedra sharing corners to form a three-dimensional framework containing two types of tunnels running along the c axis, in which the sodium ions are located. Na(+) catio...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Acta Crystallographica Section A Foundations of Crystallography
سال: 2008
ISSN: 0108-7673
DOI: 10.1107/s0108767308084985