Crystal Structures and Adsorption Spectra of Heterometal Mono-Dimensional Hexanuclear Complexes with no Bridge Assisted Rhodium-Platinum Bonds
Crystal Structures and Adsorption Spectra of Heterometal Mono-Dimensional Hexanuclear Complexes with no Bridge Assisted Rhodium-Platinum Bonds
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无桥辅助铑-铂键异金属单维六核配合物的晶体结构和吸附光谱
DOI：
10.1016/j.poly.2012.06.091
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发表时间：
2012
期刊：
影响因子：
2.6
通讯作者：
M. Ebihara
中科院分区：
文献类型：
--
作者：
K. Uemura;K. Sakurai;E. Yasuda;M. Ebihara
作为先前化合物[{Rh 2（O2 CCH 3）4}{Pt 2（piam）2（NH3）4}2]n（PF 6）4 n·6 nH 2 O的类似物（1，其中piam=新戊酰胺），两个六核配合物[{Rh 2（O2 CCH 3）4}{Pt 2（piam）2（NH 2CH 3）4}2]（PF 6）4（2）和[{Rh 2（O2 CCH 3）4}{Pt 2（piam）2（bpy）2}2]（PF 6）4（3，bpy= 2，2 ′-bipyridine）的合成方法是将[Rh 2（O2 CCH 3）4]配合物（即，[Rh 2]）与两个含有不同共配体的新戊酰胺桥联铂络合物（即，[Pt2]）。单晶X射线衍射分析表明，[Pt 2]通过[Rh 2]与金属-金属键连接，形成[Pt 2]-[Rh 2]-[Pt 2]的线性排列。考虑到金属-金属距离、元素分析和X射线光电子能谱（XPS），2和3中的每种金属的氧化态可以被认为是[Pt 2 II，II]-[Rh 2 II，II]-[Pt 2 II，II]，其与起始化合物中的氧化态相同。这些六核骨架是由于[Rh 2]和[Pt 2]之间的氢键以及[Rh 2 II，II]中的空位σ π和[Pt 2 II，II]中的填充σ π之间的HOMO-LUMO相互作用导致的非桥Rh-Pt键的形成。2和3的电子吸收光谱表明，[Rh 2（O2 CCH 3）4]的Rh 2核中出现了3个新峰E1，E2和E3，而不是原来的π π（Rh 2）→σ π（Rh-O）和π π π（Rh 2）→σ π（Rh 2）跃迁，表明Rh和Pt原子之间存在金属-金属相互作用.
As analogues to a previous compound [{Rh2(O2CCH3)4}{Pt2(piam)2(NH3)4}2]n(PF6)4n·6nH2O (1, where piam=pivalamidate), two hexanuclear complexes [{Rh2(O2CCH3)4}{Pt2(piam)2(NH2CH3)4}2](PF6)4(2) and [{Rh2(O2CCH3)4}{Pt2(piam)2(bpy)2}2](PF6)4(3, bpy=2,2′-bipyridine) have been synthesized by following a simple procedure of mixing separately, a [Rh2(O2CCH3)4] complex (i.e., [Rh2]) with two pivalamidate-bridged platinum complexes containing different co-ligands (i.e., [Pt2]). Single-crystal X-ray analyses for 2 and 3 reveal that [Pt2] is linked by [Rh2] with metal–metal bonds to form a linear alignments of [Pt2]–[Rh2]–[Pt2]. Taking into account for the metal–metal distances, elemental analyses, and X-ray photoelectron spectra (XPS), the oxidation state of each metal in 2 and 3 can be considered as being [Pt2II,II]–[Rh2II,II]–[Pt2II,II], which is unchanged from that in the starting compounds. These hexanuclear backbones are attributed to easily formation of unbridged Rh–Pt bonds, which are caused not only by hydrogen bonds of ligands between [Rh2] and [Pt2], but also HOMO–LUMO interaction between vacant σ∗in [Rh2II,II] and filled σ∗in [Pt2II,II]. Electronic absorption spectra of 2 and 3 show three new peaks E1, E2, and E3involved with σ-type orbitals, instead of original ones, π∗(Rh2)→σ∗(Rh–O) and π∗(Rh2)→σ∗(Rh2) transitions in the Rh2core of [Rh2(O2CCH3)4], revealing the presence of metal–metal interactions between Rh and Pt atoms.