Silylamides special

The present article will focus in particular on structurally characterized complexes and will refer to current trends and potential applications, simultaneously aiming at a coherent picture of the entire family of organometallic lanthanide amides including the inorganic derivatives. The elements Sc, Y, La will be treated as lanthanide elements Ln. Previous reviews cover this subject mostly as an aspect wrapped up under a comprehensive depiction of both metal amides [19] and lanthanide chemistry [20]. Other articles focus on special topics in this field, e.g., inorganic amides [21], silylamides [22], phthalocyanines [23] or porphyrins [24],... 

A depending on the size of the lanthanide metals. Delocalization of electron density on four equivalent nitrogen atoms causes elongation of the Ln-N bonds at about 0.10-0.15 A compared to silylamides. The close proximity of the macrocyclic 7i-systems in sandwich complexes proved to be useful as structural and spectroscopic models for the bacteriochlorophyll [Mg(Bchl)]2, the special pair in the reaction center of bacterial photosynthesis [211,212]. The distance between the pyrrole rings in [Mg(Bchl)]2 is about 3 A. 

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