Results for “NiIr” | Engineering Papers

DOE OSTI2021

Spin-liquid behavior of the three-dimensional magnetic system Ba 3 NiIr 2 O 9 with S = 1

The quantum spin liquid (QSL) is an exotic phase of magnetic materials where the spins continue to fluctuate without any symmetry breaking down to zero temperature. Among the handful reports of QSL with spin S ≥ 1, examples with magnetic ions on a three-dimensional (3D) magnetic lattice are extremely rare since both larger spin and higher dimension tend to suppress quantum fluctuations. In this work, we offer a new strategy to achieve 3D QSL with high spin by utilizing two types of transition metal ions; both are magnetically active but located at crystallographically inequivalent positions. Furthermore, we design a 3D magnetic system Ba 3 NiIr 2 O 9 consisting of interconnected corner-shared NiO 6 octahedra and face-shared Ir 2 O 9 dimer, both having triangular arrangements in a-b plane. X-ray absorption spectroscopy measurements confirm the presence of Ni 2+ (S = 1). Furthermore, our detailed thermodynamic and magnetic measurements reveal that this compound is a realization of gapless QSL state down to at least 100 mK. Ab initio calculations find a strong magnetic exchange between Ir and Ni sublattices and in-plane antiferromagnetic coupling between the dimers, resulting in dynamically fluctuating magnetic moments.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2020

Materials Data on NiIr by Materials Project

IrNi crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are three inequivalent Ir sites. In the first Ir site, Ir is bonded to six equivalent Ir and six equivalent Ni atoms to form distorted IrNi6Ir6 cuboctahedra that share corners with twelve IrNi6Ir6 cuboctahedra, edges with twelve IrNi6Ir6 cuboctahedra, edges with twelve equivalent NiNi6Ir6 cuboctahedra, faces with six equivalent IrNi6Ir6 cuboctahedra, and faces with twelve equivalent NiNi6Ir6 cuboctahedra. All Ir–Ir bond lengths are 2.68 Å. All Ir–Ni bond lengths are 2.60 Å. In the second Ir site, Ir is bonded to six equivalent Ir and six Ni atoms to form distorted IrNi6Ir6 cuboctahedra that share corners with five equivalent NiNi10Ir6 cuboctahedra, corners with twelve IrNi6Ir6 cuboctahedra, edges with ten NiNi6Ir6 cuboctahedra, edges with twelve IrNi6Ir6 cuboctahedra, faces with six equivalent IrNi6Ir6 cuboctahedra, and faces with fifteen NiNi6Ir6 cuboctahedra. All Ir–Ir bond lengths are 2.68 Å. All Ir–Ni bond lengths are 2.60 Å. In the third Ir site, Ir is bonded to six equivalent Ir and six Ni atoms to form distorted IrNi6Ir6 cuboctahedra that share corners with five equivalent NiNi10Ir6 cuboctahedra, corners with twelve IrNi6Ir6 cuboctahedra, edges with ten NiNi6Ir6 cuboctahedra, edges with twelve IrNi6Ir6 cuboctahedra, faces with six equivalent IrNi6Ir6 cuboctahedra, and faces with fifteen NiNi6Ir6 cuboctahedra. All Ir–Ir bond lengths are 2.68 Å. All Ir–Ni bond lengths are 2.60 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded to six Ir and six equivalent Ni atoms to form distorted NiNi6Ir6 cuboctahedra that share corners with twelve NiNi6Ir6 cuboctahedra, edges with twelve IrNi6Ir6 cuboctahedra, edges with twelve NiNi6Ir6 cuboctahedra, faces with six equivalent NiNi6Ir6 cuboctahedra, and faces with twelve IrNi6Ir6 cuboctahedra. All Ni–Ni bond lengths are 2.68 Å. In the second Ni site, Ni is bonded to six Ir and ten equivalent Ni atoms to form distorted NiNi10Ir6 cuboctahedra that share corners with ten IrNi6Ir6 cuboctahedra, corners with twelve NiNi6Ir6 cuboctahedra, edges with eight IrNi6Ir6 cuboctahedra, edges with sixteen NiNi6Ir6 cuboctahedra, faces with sixteen equivalent NiNi10Ir6 cuboctahedra, and faces with eighteen IrNi6Ir6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.68–5.35 Å.

36 MATERIALS SCIENCE↗