title: Density functional analysis of the magnetic structure of Li3RuO4: importance of the Ru-O···O-Ru spin-exchange interactions and substitutional Ru defects at the Li sites.
abstract: We evaluated the spin-exchange interactions of Li(3)RuO(4) by performing energy-mapping analysis based on density functional calculations and examined the nature of its magnetic transition at T(1) = 66 K and the divergence of the field-cooled and zero-field-cooled susceptibilities below T(2) = 32 K. Our study shows that T(1) is associated with a three-dimensional antiferromagnetic ordering, in which the two-dimensional antiferromagnetic lattices parallel to the ab plane are antiferromagnetically coupled along the c direction. We examined how the substitutional defects, Ru atoms residing in the Li sites, affect the antiferromagnetic coupling along the c direction to explain why the expected c-axis doubling is not detected from powder neutron diffraction measurements. The susceptibility divergence below T(2) is attributed to a slight spin canting out of the ab plane.
authors.affiliation: Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
authors.forename: Won-Joon
authors.initials: WJ
authors.lastname: Son
authors.forename: Pascal
authors.initials: P
authors.lastname: Manuel
authors.forename: Devashibhai
authors.initials: D
authors.lastname: Adroja
authors.forename: Myung-Hwan
authors.initials: MH
authors.lastname: Whangbo