METAL-ORGANIC FRAMEWORKS halides

Silicon, as the heavier homolog of carbon, is fourfold coordinated in its compounds in most cases. This is, for example, reflected by the chemistry of silicates [1]. In these naturally occurring compounds, the silicon atoms are almost exclusively found in Si04-coordination. The situation is similar for synthetic solids, such as extended binary phases like pure silica zeolite-type frameworks [2], SiS2, SiC or Si3N4, and related more complex ternary and multinary solids [3], This is also valid for molecular silicon halides, hydrides, and metal organic (e.g., silicon alkoxides) as well as organometaUic silicon compounds [3, 4],... 

Mitzi, D.B. Liang, K.N. Preparation and properties of (C4H9NH3)2Eul4 A luminescent organic-inorganic perovskite with a divalent rare-earth metal halide framework. Chem. Mater. 1997, 9, 2990. 

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