Effect of alkali cations on two-dimensional networks of two new quaternary thioarsenates (III) prepared by a facile surfactant-thermal method
Two new quaternary thioarsenates(III) NaAg{sub 2}AsS{sub 3}·H{sub 2}O (1) and KAg{sub 2}AsS{sub 3} (2) with high yields have been successfully prepared through a facile surfactant-thermal method. It is interesting that 2 can only be obtained with the aid of ethanediamine (en), which indicates that weak basicity of solvent is beneficial to the growth of 2 compared with 1. Both 1 and 2 feature the similar two-dimensional (2D) layer structures. However, the distortion of the primary honeycomb-like nets in 2 is more severe than that of 1, which demonstrates that Na{sup +} and K{sup +} cations have different structure directing effects on these two thioarsenates(III). Both experimental and theoretical studies confirm 1 and 2 are semiconductors with band gaps in the visible region. Our success in preparing these two quaternary thioarsenates(III) proves that surfactant-thermal technique is a powerful yet facile synthetic method to explore new complex chalcogenides. - Graphical abstract: Two new quaternary thioarsenates(III) NaAg{sub 2}AsS{sub 3}·H{sub 2}O (1) and KAg{sub 2}AsS{sub 3} (2) with high yields have been successfully prepared through a facile surfactant-thermal method. X-ray single crystal diffraction analyses demonstrate that Na{sup +} and K{sup +} cations have different structure directing effects on these two thioarsenates(III). Both experimental and theoretical studies confirm 1 and 2 are semiconductors with band gaps in the visible region. Display Omitted - Highlights: • NaAg{sub 2}AsS{sub 3}⋅H{sub 2}O (1) and KAg{sub 2}AsS{sub 3} (2) were prepared through surfactant-thermal method. • Crystal structures show Na{sup ±} and K{sup ±} have different structure directing effects. • The weak basicity of solvent is benefit to the growth of 2 compared with 1. • Experimental and theoretical studies confirm 1 and 2 are semiconductors.