Английская Википедия:Europium(II) iodide
Europium(II) iodide is the iodide salt of divalent europium cation.
Preparation
Europium(II) iodide can be prepared in a handful of ways, including:
Reduction of europium(III) iodide with hydrogen gas at 350 °C:[1]
Thermal decomposition of europium(III) iodide at 200 °C:[1]
Reaction of europium with mercury(II) iodide:[1]
Reaction of europium with ammonium iodide:[1]
Structure
Europium(II) iodide has several polymorphs.[2] It adopts a monoclinic crystal structure in space group P 21/c (no. 14).[3][4]
It also adopts an orthorhombic polymorph in space group Pbca (no. 61). This form is isostructural with strontium iodide.[5]
A third polymorph of europium(II) iodide is formed if it is prepared from europium and ammonium iodide at low temperatures (200 K) in liquid ammonia. This low-temperature phase is orthorhombic and in space group Pnma (no. 62). This is the same structure as modification IV of strontium iodide.[6]
References
Шаблон:Europium compounds Шаблон:Iodides Шаблон:Lanthanide halides
Шаблон:Inorganic-compound-stub
