Ca3Sm3[Si9N17] and Ca3Yb3[Si9N17] Nitridosilicates with Interpenetrating Nets that Consist of Star‐Shaped [N[4](SiN3)4] Units and [Si5N16] Supertetrahedra
Sie können Bookmarks mittels Listen verwalten, loggen Sie sich dafür bitte in Ihr SLUB Benutzerkonto ein.
Medientyp:
E-Artikel
Titel:
Ca3Sm3[Si9N17] and Ca3Yb3[Si9N17] Nitridosilicates with Interpenetrating Nets that Consist of Star‐Shaped [N[4](SiN3)4] Units and [Si5N16] Supertetrahedra
Beschreibung:
<jats:title>Abstract</jats:title><jats:p>New nitridosilicates Ca<jats:sub>3</jats:sub>Sm<jats:sub>3</jats:sub>[Si<jats:sub>9</jats:sub>N<jats:sub>17</jats:sub>] and Ca<jats:sub>3</jats:sub>Yb<jats:sub>3</jats:sub>[Si<jats:sub>9</jats:sub>N<jats:sub>17</jats:sub>] were synthesized from the reactions of the pure metals (calcium and samarium/ytterbium) with silicon diimide “Si(NH)<jats:sub>2</jats:sub>” in a radio‐frequency (rf) furnace at temperatures of up to 1650 °C. These isotypic compounds crystallize in the cubic space group <jats:italic>P</jats:italic><jats:styled-content>$\bar 4$<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-ueqn-1.gif" xlink:title="equation image" /></jats:styled-content>3<jats:italic>m</jats:italic> (no. 215) with lattice parameters <jats:italic>a</jats:italic>=739.50(3) pm; <jats:italic>V</jats:italic>=0.4044(1) nm<jats:sup>3</jats:sup>; <jats:italic>Z</jats:italic>=1; <jats:italic>wR</jats:italic><jats:sub>2</jats:sub>=0.029 (240 diffraction data, 26 parameters) for Ca<jats:sub>3</jats:sub>Sm<jats:sub>3</jats:sub>[Si<jats:sub>9</jats:sub>N<jats:sub>17</jats:sub>] and <jats:italic>a</jats:italic>=730.20(2) pm; <jats:italic>V</jats:italic>=0.3893(1) nm<jats:sup>3</jats:sup>; <jats:italic>wR</jats:italic><jats:sub>2</jats:sub>=0.039 (387 diffraction data, 27 parameters) for Ca<jats:sub>3</jats:sub>Yb<jats:sub>3</jats:sub>[Si<jats:sub>9</jats:sub>N<jats:sub>17</jats:sub>]. The new structure type of Ca<jats:sub>3</jats:sub><jats:italic>RE</jats:italic><jats:sub>3</jats:sub>[Si<jats:sub>9</jats:sub>N<jats:sub>17</jats:sub>] (<jats:italic>RE</jats:italic>=Sm, Yb) consists of two independent infinite networks, each of which have an expanded sphalerite (ZnS) topology in which the positions of the Zn and S atoms are replaced by voluminous [N<jats:sup>[4]</jats:sup>(SiN<jats:sub>3</jats:sub>)<jats:sub>4</jats:sub>] units and [Si<jats:sub>5</jats:sub>N<jats:sub>16</jats:sub>] supertetrahedra, respectively, thereby displaying twofold interpenetration. As well, a structural description of Ca<jats:sub>3</jats:sub>Yb<jats:sub>3</jats:sub>[Si<jats:sub>9</jats:sub>N<jats:sub>17</jats:sub>], its thermal stability, and magnetic properties, as well as UV/Vis, IR, and Raman spectra, are presented.</jats:p>