Spatially anisotropic S = 1 square-lattice antiferromagnet with single-ion anisotropy realized in a Ni(II) pyrazine-n, n'-dioxide coordination polymer

Journal article

The Ni(NCS)₂ (pyzdo)₂ coordination polymer is found to be an S = 1 spatially anisotropic square lattice with easy-axis single-ion anisotropy. This conclusion is based upon considering in concert the experimental probes x-ray diffraction, magnetic susceptibility, magnetic-field-dependent heat capacity, muon-spin relaxation, neutron diffraction, neutron spectroscopy, and pulsed-field magnetization. Long-range antiferromagnetic (AFM) order develops at T_N = 18.5K. Although the samples are polycrystalline, there is an observable spin-flop transition and saturation of the magnetization at ≈80 T. Linear spin-wave theory yields spatially anisotropic exchanges within an AFM square lattice, J_x =0.235 meV, J_y =2.014 meV, and an easy-axis single-ion anisotropy D = −1.622 meV (after renormalization). The anisotropy of the exchanges is supported by density functional theory.

Authors: Manson, JL; Pajerowski, DM; Donovan, JM; Twamley, B; Goddard, PA

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review B
• Volume: 108
• Issue: 9
• Article number: 094425
• Publication date: 2023-09-14
• Acceptance date: 2023-08-16
• DOI: 10.1103/PhysRevB.108.094425
• EISSN: 2469-9969
• ISSN: 2469-9950
• Language: English
• Keywords: inelastic neutron scattering; specific heat measurements; magnetism; x-ray diffraction; magnetization measurements; linear spin wave theory; neutron diffraction; inorganic chemistry; density matrix renormalization group; antiferromagnetism; DC susceptibility measurements; density functional theory; muon spin relaxation and rotation; time-of-flight neutron spectroscopy; 2-dimensional systems