Selected Publications

Magnetic structure and dynamics of a strongly one-dimensional cobaltII metal-organic framework

R. Sibille, E. Lhotel, T. Mazet, B. Malaman, C. Ritter, V. Ban, and M. Francois

We investigate the magnetism of the CoII4(OH)2(C10H16O4)3 metal-organic framework, which displays complex inorganic chains separated from each other by distances of 1 to 2 nm and orders at 5.4 K. The zero-field magnetic structure is determined using neutron powder diffraction: it is mainly antiferromagnetic but possesses a ferromagnetic component along the c axis. This magnetic structure persists in presence of a magnetic field.Alternating current susceptibility measurements confirm the existence of a single thermally activated regime over seven decades in frequency (E/kB ≈ 64 K), whereas time-dependent relaxation of the magnetization after saturation in an external field leads to a two times smaller energy barrier. These experiments probe the slow dynamics of domain walls within the chains: we propose that the ac measurements are sensitive to the motion of existing domain walls within the chains, while the magnetization measurements are governed by the creation of domain walls.

Phys. Rev. B 89, 104413 (2014)

doi: 10.1103/PhysRevB.89.104413