Synthesis, Structure, and Optical Properties of a Molecular Cluster Cd₄(<i>p</i>-MBT)₁₀

Abstract

The creation of atomically precise nanoclusters has become an important research direction in nanoscience, because such nanomaterials can demonstrate unique chemo-physical properties that are significantly different from their corresponding bulk materials. The cause of such disparities lies in their different construction pattern for the atomic structures, in which the bulk materials display a highly symmetric, extended atomic lattice, while the ultrasmall nanoclusters feature low symmetric molecular structures. In this work, we report a new [HNEt3]2[Cd4(SC7H7)10] (denoted as Cd4(p-MBT)10, p-MBT = p-methylbenzene thiolate) nanocluster obtained through a one-pot synthetic pathway, and its atomic structure was revealed by single crystal X-ray diffraction technique. It shows that the molecular structure for Cd4(p-MBT)10 demonstrates the embryonic features of the corresponding bulk CdS. That is, the whole structure is built from four [CdS4] units which are connected to each other by shared corner S atoms. Due to the molecular nature, the structure of Cd4(p-MBT)10 is distorted, which yields two enantiomeric isomers with chiral Cd-S frameworks that co-crystallize into a non-chiral space group. In addition, the electronic structure was characterized by photoluminescence spectroscopy and calculated by density functional theory.

Keywords

• cadmium sulfide
• single crystal
• semiconducting nanocluster
• nanocluster synthesis