Four CuI(ett) coordination polymorphs and changes in XRD upon hydrothermal condition optimization

Abstract

Four [Cu^I(ett)]_n coordination polymorphs (1-α, 1-β, 1-γ and 1-δ), based on 5-(ethylthio)-1H-tetrazole (Hett), have been prepared successfully. By regulating the reaction time and reaction temperature, the rich coordination mode of the ett ligands can be regulated. Consequently, 1-α, 1-β and 1-γ show 2D wave-like layers, while 1-δ shows a 3D network. Powder X-ray diffraction (PXRD) analysis of the bulk sample of 1 prepared through a hydrothermal procedure revealed that 1-α and 1-δ can be isolated through temperature-dependent and time-dependent experiments, respectively. Starting from an as-prepared sample of 1-α in aqueous solution, the conversion from 1-α to 1-δ has been tracked over time by PXRD, with observations of the intermediate phases of 1-β and/or 1-γ in the hydrothermal re-crystallization process.