Crystal structure of Ag 3 Dy 2 (NO 3 ) 9 and qu-anti-tative comparison to isotypic compounds.

Single crystals of Ag 3 Dy 2 (NO 3 ) 9 (tris-ilver didysprosium nona-nitrate) were obtained from a mixture of AgNO 3 and Dy(NO 3 ) 3 ·5 H 2 O. The new compound crystallizes in space group P 4 1 32 (No. 213) with a = 13.2004 (4) Å, V = 2300.2 (2) Å 3 , Z = 4. The Ag and Dy cations are coordinated by five and six bidentate nitrate anions, respectively. Ag 3 Dy 2 (NO 3 ) 9 is isostructural to several compounds that include alkali metals or ammonium and lanthanide cations, but silver and dysprosium are included for the first time and feature the smallest ion radii observed for this structure type to date. Crystal structures of isotypic compounds are compared.