A Discrete Ligand-Free T3 Supertetrahedral Cluster of Gallium Sulfide

Abstract

Large discrete supertetrahedral clusters of metal chalcogenides are rare due to the difficulty of crystallizing solids in which the negative charge of the cluster is balanced by the positive charges of the countercations. Here, we describe a discrete ligand-free T3 supertetrahedral cluster, [Ga10S16(SH)4]6−, which was successfully synthesized in the presence of the superbase 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) using the neutral surfactant polyethyleneglycol (PEG)-400 as the reaction solvent. Protonated DBUH+ cations are incorporated into the crystal structure of the product, which can be formulated as [C9H17N2]6[Ga10S16(SH)4]. This compound, which represents the first example of a discrete ligand-free T3 cluster of gallium sulfide, was fully characterized by single-crystal and powder X-ray diffraction, elemental analysis, infrared spectroscopy, thermogravimetric analysis, and ultraviolet-visible diffuse reflectance. The results presented here indicate that the use of surfactants as solvents offers potential for the preparation of new compounds containing supertetrahedral clusters.

Crystalline chalcogenidometalate-based compounds from uncommon reaction media

“…13,102,103 In 2021, the first isolation of a discrete, ligand-free T3-type sulfidogallate cluster was documented to form in a surfactantthermal reaction, which further expanded the family of Ga/S clusters. 104…”

Selective and benign alkylation of sulfido-oxo stannate clusters with propyl, pentyl, or hexyl substituents

“…3 In addition, compounds comprising discrete sulfido stannate cluster molecules have attracted particular attention owing to their tunable electronic and optical properties that can be varied with the cluster size 4 and exact composition of the molecules. 5–7…”

“…3 In addition, compounds comprising discrete sulfido stannate cluster molecules have attracted particular attention owing to their tunable electronic and optical properties that can be varied with the cluster size 4 and exact composition of the molecules. [5][6][7] Most of these compounds have traditionally been accessed by molten flux [8][9][10][11] approaches or high temperature syntheses, before hydrothermal 12 or aminothermal 13 approaches were added as synthesis methods. 12 The most recent technique for their preparation, however, utilizes ionic liquids under so-called ionothermal conditions, which again expanded the chemical and structural diversity of crystalline chalcogenides in general, and sulfido stannate cluster compounds in particular.…”