Mixed pentasupertetrahedral P1 and supertetrahedral T2 clusters as building units to create two-dimensional indium chalcogenides open framework

► A new 2-D open framework [In12S21(Se)3H2], NCYU-5, is constructed from P1, and T2 clusters. ► The guest molecule (TMDP) can be exchanged by (Na+, K+), and (Mg2+, Ca2+, Sr2+, Ba2+) up to (Ba/Se) =12.05%. ► The luminescent output from the NCYU-5 exhibits a shift from λmax = 433 nm (77K) to λmax = 450 nm (298 K).