Ghimire Mukunda M, Nesterov Vladimir N, Omary Mohammad A
Department of Chemistry, University of North Texas , Denton, Texas 76203, United States.
Inorg Chem. 2017 Oct 16;56(20):12086-12089. doi: 10.1021/acs.inorgchem.7b01679. Epub 2017 Sep 28.
A new aurophilically-bonded cyclic trinuclear gold(I) complex, tris[μ-(1-ethylimidazolato-N,C)gold(I)] ([Au(EtIm)], 1), has been synthesized and characterized by temperature-dependent crystallographic and photophysical investigations. The crystal packing of 1 reveals two independent molecules in the unit cell, signifying two distinct pairs of dimer-of-trimer units convened by pairwise intermolecular Au···Au interactions of 3.0662(3) and 3.1407(3) Å at 100 K, representing the shortest pairwise intermolecular aurophilic interactions among all cyclic trimetallic gold(I) complexes to date. Remarkably, crystals of 1 exhibit gigantic photoluminescence thermochromism of 10164 cm-from violet to red!-attributed to internal conversion between a higher-energy (T → S; λ ∼409 nm) and lower-energy (T → S; λ ∼700 nm) phosphorescent band below and above 200 K, respectively, likely representing an excited-state phase change.
一种新的具有金亲合键的环状三核金（I）配合物，三[μ-（1-乙基咪唑-N，C）金（I）]（[Au（EtIm）]，1），已通过温度相关的晶体学和光物理研究进行了合成和表征。1的晶体堆积在晶胞中显示出两个独立的分子，这意味着在100K时，由3.0662（3）和3.1407（3）Å的分子间Au···Au相互作用形成了两种不同的三聚体二聚体对，这是迄今为止所有环状三金属金（I）配合物中最短的分子间金亲合相互作用。值得注意的是，1的晶体表现出10164cm-1的巨大光致发光热致变色，从紫色变为红色！这归因于分别在200K以下和以上的高能（T→S；λ∼409nm）和低能（T→S；λ∼700nm）磷光带之间的内转换，这可能代表了一种激发态相变。
