New representatives with BaAl4, La3Al11 and BaHg11 structure types from the R–Zn–Ga systems (R = Y, Lu, Gd–Tm)

Fifteen new ternary RZn2−xGa2+x, R3Zn11−xGax and RZn11−xGax (R = Y, Lu, Gd–Tm) compounds have been synthesized by reacting the elements at 960 °C, followed by annealing at 400 °C. The crystal structure of all the compounds was solved from powder X-ray counter data and their compositions were confirmed by EDS analysis. Additionally, single crystal X-ray diffraction studies were also performed for the DyZn8.6Ga2.4 phase. It was found that the new compounds crystallize with BaAl4, La3Al11 and BaHg11 structure types, respectively.

► New ternary phases RZn2−xGa2+x, R3Zn11−xGax and RZn11−xGax (R = Y, Lu, Gd – Tm) have been indentified at 400°C in the R–Zn–Ga systems. ► Investigated gallides crystallize in tetragonal BaAl4 (space group I4/mmm), orthorhombic La3Al11 (space group Immm) and BaHg11 (space group Pm  3¯m) structure types, respectively. ► Coordination of the atoms, interatomic distances and relation with other structures of above mentioned compounds have been discussed.