Details

Autor(en) / Beteiligte

• Lupart, Saskia
• Zeuner, Martin
• Pagano, Sandro
• Schnick, Wolfgang

Titel

Chain-Type Lithium Rare-Earth Nitridosilicates - Li5Ln5Si4N12 with Ln = La, Ce

Ist Teil von

• European Journal of Inorganic Chemistry, 2010, Vol.2010 (18), p.2636-2641

Ort / Verlag

Weinheim: WILEY-VCH Verlag

Erscheinungsjahr

2010

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The quaternary lithium rare‐earth nitridosilicates Li5Ln5Si4N12 with Ln = La, Ce were synthesized at moderate temperatures below 900 °C in closed tantalum ampoules employing liquid lithium as a flux. Thereby, nitridosilicate substructures with a low degree of condensation were obtained. The air and moisture sensitive title compounds are the first representatives of quaternary lithium rare‐earth nitridosilicates and crystallize in space group P$\bar {4}$b2 [Li5La5Si4N12: a = 1104.28(16), c = 557.30(11) pm, Z = 2, R1 = 0.0498, 873 data, 56 parameters; Li5Ce5Si4N12: a = 1097.78(16), c = 551.43(11) pm, Z = 2, R1 = 0.0334, 748 data, 56 parameters]. The nitridosilicate substructure consists of infinite nonbranched zweier single‐chains of vertex sharing SiN4 tetrahedra running parallel to [001]. The chains exhibit a stretching factor fS = 0.981 for La and 0.977 for Ce, respectively. The two crystallographically independent Li+ sites are each coordinated by four nitrogen atoms. Lattice energy calculations (MAPLE) and EDX measurements confirmed the electrostatic bonding interactions and the chemical compositions. For the La containing compound 7Li solid‐state MAS NMR investigations are reported. Two new quaternary lithium rare earthnitridosilicates Li5Ln5Si4N12 (Ln = La, Ce) with nonbranched SiN4 zweier single‐chains have been characterized. The method of using lithium melts in closed systems at moderate temperatures has been extended to the synthesis of rare earthelement containing compounds. The 7Li solid‐state NMR spectrum of Li5La5Si4N12 is reported.