Crystal chemical features of ternary phases in the R-Li-Ge (RÂ =Â rare earth element) systems

► R4LiGe4, R3Li4Ge4 and R7Li8Ge10 (R = La-Nd, Sm) are synthesized and characterized. ► Compounds with formula R7Li8Ge10 crystallize in a new orthorhombic structure type. ► R3Li4Ge4 and Pr7Li8Ge10 are built with fragments of the MgCuAl2 and AlB2 types. ► All R-Li-Ge compounds show the trigonal prismatic coordination around Ge.