[Zn10(mu4-S)(mu3-S)6(Py)9(SO4)3] as a molecular model of ZnS surfaces: an experimental and theoretical study

Experimental and theoretical results pertaining to [Zn-10(mu(4)-S)(mu(3)-S)(6)(Py)(9)(SO4)(3)], a possible molecular model of ZnS S-terminated polar surfaces, as well as a potential source of strictly monodispersed ZnS quantum dots, are presented and discussed. The results of density functional theory (DFT) calculations provided a rationale for the peculiar arrangement of [Zn-10(mu(4)-S)(mu(3)-S)(6)(Py)(9)(SO4)(3)] clusters in the solid state, contemporarily indicating the unsuitability of the isolated species to mimic whatever (polar or non-polar) ZnS surface. Despite the fact that such a failure is further confirmed by time-dependent DFT and UV-Vis diffuse reflectance spectroscopy, the combined use of theoretical outcomes, DRIFT measurements, and literature data pertaining to the surface chemical properties of ZnS (Hertl in Langmuir 4:594, 1988) ultimately testifies that [Zn-10(mu(4)-S)(mu(3)-S)(6)(Py)(9)(SO4)(3)] is perfectly suited to model the interaction of pyridine molecules with ZnS surface Lewis acid sites. The herein reported theoretical results are expected to be a useful reference for the interpretation of chemisorption experiments of Py-based Lewis bases on single crystal ZnS surfaces.