Abstract Ba 4LaGe 3SbSe 13 was prepared by reacting the elements under exclusion of air at 700°C, followed by slow cooling to room temperature. It crystallizes in a new type of the monoclinic space group P2 1/ c, with lattice dimensions of a=1633.30(9) pm, b=1251.15(7) pm, c=1303.21(7) pm, β=103.457(2)°, V=2590.0(2) 10 6 pm 3 ( Z=4). The structure contains isolated GeSe 4 as well as Ge 2Se 7 digermanate units. Two of the latter are interconnected via an Sb 2Se 4 bridge yielding an almost linear complex anion [Ge 2Se 7–Sb 2Se 4–Ge 2Se 7] 14−. The oxidation states are assigned to be Ba II, La III, Ge IV, Sb III, and Se −II, in accord with an electronically saturated nonmetal. The lone pair of Sb III reflects itself in highly irregular Se coordination. The red color of the material is indicative of semiconducting behavior with an activation energy of 2.0 eV. Electronic structure calculations based on the LMTO approximation point to a smaller gap, typical for this calculation method. We utilized the COHP tool to explore the bonding character of the different Sb–Se interactions.