By combining different oxidation states, coordination indices and bridging systems, it has been possible to obtain the structurally novel M₄(OH)₄ cluster core (M = transition metal) found in the organometallic compound (NBu₄)₂[Pt^IVPt^II₃(C₆Cl₅)₈(μ₂-OH)₂(μ₃-OH)₂] (1). The cluster is formed by two (μ₃-OH) and two (μ₂-OH) units that bond platinum atoms in different oxidation states. The cluster core geometry can best be described as a half-hexagram. Compound 1 is an excellent precursor for preparing heterometallic clusters since it can host d¹⁰ or s² Lewis-acid metal centers through Pt→M dative bonds, as demonstrated by its reaction with Ag(I) to produce the heterometallic [Ag₂Pt^IVPt^II₃(C₆Cl₅)₈(μ₂-OH)₂(μ₃-OH)₂] (2), which has four unbridged Pt–Ag bonds.

中文翻译：

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通往小型集群的途径：扭曲的半六角形M ₄（OH）₄集群及其容纳封闭壳金属的能力

通过组合不同的氧化态，配位指数和桥联体系，有可能获得有机金属化合物（NBu ₄）₂ [Pt ^IV Pt ^II ]中发现的结构新颖的M ₄（OH）₄簇核（M =过渡金属）。₃（C ₆氯₅）₈（μ ₂ -OH）₂（μ ₃ -OH）₂ ]（1）。群集由两个（μ形成₃ -OH）和两个（μ ₂-OH）单元以不同的氧化态键合铂原子。簇芯的几何形状可以最好地描述为半六边形。化合物1是制备异金属簇的极好前体，因为它可以通过Pt→M配位键容纳d ¹⁰或s ^2个路易斯酸金属中心，这与它与Ag（I）反应生成异金属[Ag ₂ Pt ^IV的Pt ^II ₃（C ₆氯₅）₈（μ ₂ -OH）₂（μ ₃ -OH）₂ ]（2），其具有四个未桥连的Pt-银键。