Design and synthesis of Ba3SiSe5 with suitable birefringence modulated via MIV atoms in the Ba–MIV–Q (MIV = Si, Ge; Q = S, Se) system

A new ternary Ba-based selenide, Ba 3 SiSe 5 , featuring isolated SiSe 4 tetrahedra and exhibiting moderate birefringence, has been synthesized and characterized for the first time.