Abstract
We report on thermodynamic properties of both rhombohedral R (3) over bar and cubic Ia (3) over bar phases of Yb6MoO12-delta supplemented by measurements of Lu6MoO12-delta(R (3) over bar) magnetic properties. Among these series, Yb6MoO12-delta(R (3) over bar) only exhibits signatures of magnetic long-range order at T-N similar to 2.5 K which is confirmed by both physical property measurements and neutron powder diffraction. Low temperature specific heat measured down to 100 mK suggests the rearrangement of magnetic subsystem at T* = 500 mK. (C) 2018 Elsevier B.V. All rights reserved.