Controlling Lewis basicity in polythioarsenate fluxes: stabilization of KSnAsS (sub)5 and K (sub)2 SnAs (sub)2 S (sub)6. Extended chains and slabs based on pyramidal beta-[AsS (sub)4] (super)3- and [AsS (sub)3] (super)3- units

Research has been conducted on the KSnAsS (sub)5 and K (sub)2 SnAs (sub)2 S (sub)6 low-dimensional compounds. The reactivity of Sn in the thioarsenate melts of Lewis basicity and the isolation of KSnAsS (sub)5 have been investigated and the details are reported.