Rb3[C6N7(NCN)3] • 3 H2O and Cs3[C6N7(NCN)3] • 3 H2O – Synthesis, Crystal Structure and Thermal Behavior of two Novel Alkali Melonates

Wolfgang Schnick (1) , Sophia Makowski (2)

1 Department Chemie und Biochemie
2 Department Chemie und Biochemie

Abstract. Rubidium melonate trihydrate Rb3[C6N7(NCN)3] • 3 H2O and cesium melonate trihydrate Cs3[C6N7(NCN)3] • 3 H2O were obtained by ion exchange reactions in aqueous solution. The structure of the cesium salt was determined by single-crystal X-ray diffraction (Pna21, a = 687.34(14), b = 2196.5(4), c = 1232.6(3) pm, V = 1860.9(7) • 106 pm3, Z = 4, T = 200 K). The crystal structure of the isotypic rubidium salt was refined from X-ray powder diffraction data by the Rietveld method (Pna21, a = 674.48(2), b = 2146.4(1) , c = 1207.5(1) pm, V = 1753.4(6) • 106 pm3, Z = 4, T = 298 K). In the crystal structure planar melonate ions and alkali cations as well as water molecules are arranged in alternating layers. The melonate entities are interconnected by a dense hydrogen bonding network. Rb3[C6N7(NCN)3] • 3 H2O and Cs3[C6N7(NCN)3] • 3 H2O were investigated by FTIR spectroscopy, TG and DTA measurements.

Mots clés: Physical Sciences

Wolfgang Schnick, Sophia Makowski. Rb3[C6N7(NCN)3] • 3 H2O and Cs3[C6N7(NCN)3] • 3 H2O – Synthesis, Crystal Structure and Thermal Behavior of two Novel Alkali Melonates. Journal of Inorganic and General Chemistry / Zeitschrift für anorganische und allgemeine Chemie, 2009, 635 (13-14), pp.2197. ⟨10.1002/zaac.200900232⟩. ⟨hal-00511998⟩