Determination of ground state and magnetic correlations in a quasi-one dimensional spin chain iridate Ca3CoIrO6 using neutron diffraction

Ca3CoIrO6 is a quasi-one-dimensional columnar spin-chain iridate with alternately arranged face-sharing IrO6 octahedra and CoO6 trigonal prisms along the c-axis of the structure. This compound, surprisingly, unlike its isostructural counterparts Ca3Co2O6 and Ca3CoRhO6, does not exhibit partially disordered antiferromagnetic (PDA) structure. While, the combined bulk dc, ac magnetic susceptibilities, specific heat, and isothermal remanent magnetization measurements strongly infer only spin-glass-like freezing transition at ~30 K without any signature of PDA characteristics. The zero-field µSR investigations unravel the coexistence of intrachain ferromagnetic long-range ordering below 100 K and the glassy magnetic transition below 30 K. At this point, detection of true magnetic ground state as well as the ground state Ir- and Co-spin configurations of this system is elusive, thereby warranting microscopic magnetic investigation to authenticate the nature of magnetic ordering and short-range magnetic correlations and we therefore proposed neutron diffraction study of Ca3CoIrO6 on WISH.