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Metal nitrido complexes are coordination compounds and metal clusters that contain an atom of nitrogen bound only to transition metals. These compounds are ''molecular'', i.e. discrete in contrast to the polymeric, dense nitride materials that are useful in materials science. The distinction between the molecular and solid-state polymers is not always very clear as illustrated by the materials Li6MoN4 and more condensed derivatives such as Na3MoN3. Transition metal nitrido complexes have attracted interest in part because it is assumed that nitrogen fixation proceeds via nitrido intermediates. Nitrido complexes have long been known, the first example being salts of ()−, described in the 19th century.〔J. Fritzsche, H. Struve "Ueber die Osman-Osmiumsäure" Journal für Praktische Chemie 1847, Volume 41, Issue 1, pages 97–113. 〕 ==Structural trends== Mononuclear complexes feature terminal nitride ligands, typically with short M-N distances consistent with metal ligand multiple bonds. For example, in the anion in PPh4(), the Mo-N distance is 163.7 pm. The occurrence of terminal nitrido ligands follow the patterns seen for oxo complexes: they are more common for early and heavier metals. Many bi- and polynuclear complexes are known with bridging nitrido ligands.〔Kurt Dehnicke, Joachim Strähle "Nitrido Complexes of Transition Metals" Angewandte Chemie International Edition in English August 1992, Volume 31, p. 955–978.〕 More exotic metal nitrido complexes are also possible, such as a recently reported compound containing a terminal uranium nitride (-U≡N) bond. File:OsNO3_anion.png|()−, which is isoelectronic with osmium tetroxide. File:MoNCl4_anion.png|()−, a square pyramidal Mo(VI) complex. File:W2NCl10_anion.png|()−, containing two W(VI) centres bridged by a nitrido ligand. File:Ir3N(SO4)6aq3.png|()4−, structurally related to basic iron acetate. File:Uranium_nitride_anion.png|A uranium nitrido complex. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Metal nitrido complex」の詳細全文を読む スポンサード リンク
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