Work

Probing superexchange interaction in a very hard 3d–4f single-molecule magnet by inelastic neutron scattering

Year: 2026

Type: article

Abstract: We report a combined experimental and theoretical investigation of the spin dynamics in the very hard 3d–4f single-molecule magnet (SMM) {Cr 3 Dy 3 }, where a central fluorido bridge ( µ 3 –F − ) suppresses zero-field quantum tunneling of magnetization (QTM). Utilizing inelastic neutron scattering, heat capacity and ac susceptibility techniques, we have probed the low-lying magnetic excitations and their response to applied magnetic fields in polycrystalline samples. Full ab initio calculations, incorporating the experimental data, have provided an unambiguous determination of the ferromagnetic Dy–Dy coupling ( J Dy–Dy = 0.016 meV) mediated by the µ 3 –F − bridge and antiferromagnetic Cr–Dy interactions ( J Cr–Dy = − 0.215 meV). The significant energy gap between the ferrimagnetic ground state and the lowest exchange-induced excited state (1.03 meV) provides a direct mechanistic basis for the suppression of QTM, leading to its exceptional SMM property.

Source: Journal of Physics Condensed Matter

DOI: 10.1088/1361-648x/ae9024