Structures and polarizabilities of medium-sized GanAsm clusters

► We investigate medium-sized GanAsm clusters (n + m = 17-24, n − m = 0, ±1) theoretically. ► The polarizabilities depend linearly on the volumes despite of different composition. ► The even-odd oscillation of polarizabilities disappears mainly due to isomerization. ► Ultra stability of Ga9As10 and unusual electronic properties of Ga10As11 are found.