Crystal growth and magnetic properties of the coupled alternating S=1 spin chain Sr2Ni(SeO3)3
Dr. Raman Sankar and Dr I. Panneer Muthuselvaminvestigate the structural, magnetic, and thermodynamic properties of a quasi-one-dimensional (1D) S = 1 alternating spin chain compound Sr2Ni(SeO3)3 are investigated by using synchrotron x-ray powder diffraction, magnetic susceptibility χ(H, T ), and heat capacity CP(H, T ) measurements together with density functional theory (DFT) calculations. The χ(H, T ) and CP(H, T ) data reveal long-range antiferromagnetic order at TN = 3.4(3) K and short-range order at Tm ≈ 7.8 K. The short-range magnetic order together with 95% of spin entropy release above TN signifies the importance of 1D spin correlations persisting to ∼8TN. Theoretical DFT calculations with generalized gradient approximation determine leading exchange interactions, suggesting that interchain interactions are responsible for the observed long-range magnetic ordering. In addition, the temperature-field phase diagram of Sr2Ni(SeO3)3 is determined based on the χ(T, H) and CP(T, H) data. Interestingly, a nonmonotonic phase boundary of Tm is found for an external field applied along a hard axis. Our results suggest that the ground state and magnetic behavior of Sr2Ni(SeO3 )3 rely on the interplay of single-ion anisotropy, bond alternation, and interchain interactions
Journal Links: https://link.aps.org/doi/10.1103/PhysRevB.107.214406