“…While it is relatively easy to prepare bulk quaternary HA by arc melting, it is extremely difficult to prepare quaternary HA nanoparticles with desired stoichiometry. Thus one can find only a few reports on bulk quaternary Heusler alloys containing s–p elements Ga and Al, say, Cu 50 Mn 25 Ga x Al 25− x (0 ≤ x ≤ 10), 7 Ru 2 VGa x Al 1− x (0 ≤ x ≤ 1), 8 NiMnGa 2− x Al x (0 ≤ x ≤ 2), 9 Fe 2 MnGa 1− x Al x (0 ≤ x ≤ 1), 10 and Fe 50 Mn 25 Ga x Al 25− x (0 ≤ x ≤ 10) 11 etc. alloys in the literature, with none pertaining to investigations on nanoparticles.…”