Magnetic ground state study of Co2+ stacked-honeycomb antiferromagnet: Ba2Co(PO4)2

We have explored the bulk and local probe studies on this Ba2Co(PO4)2 with stacked-honeycomb lattices of cobalt ions on the bc-plane. Through a combination of magnetic susceptibility, specific heat, and 31P NMR studies, the temperature-magnetic-field phase diagram associated with this long range magnetic ordering TN = 3 K has been mapped out. A low-temperature field-induced spin-flop transition and spin-reorientation transition below TN is found to occur at an applied field of∼3 Tesla and ∼10 Tesla respectively. The temperature dependent susceptibility curve χ(T) also shows pronounced broad peak, characteristics of the short-range magnetic ordering, with T max = 4.5 K. The combined results of heat capacity and susceptibility of Ba2Co(PO4)2 stabilize a magnetic field induce phase transition. However, for this interesting compound magnetic structure is not determined and thus WISH measurements will fill this gap. Though, we have theoretically calculated and found a magnetic ground sate as anti-Neél / stipe-order Therefore, to explore the magnetic structure of Ba2Co(PO4)2 , we would like to measure high-resolution powder neutron diffraction. Here, our interest is to perform high-resolution powder neutron diffraction experiments to determine the magnetic structure of this compound. Moreover, the Co2+ ions is in the distorted octahedral environment and are expected to have an effective spin-1/2 due to spin-orbit coupled Kramers doublet.