Magnetoelastic and structural properties of azurite Cu3(CO3)2(OH)2 from neutron scattering and muon spin rotation

摘要

Azurite, Cu3(CO3)2(OH)2, has been considered an ideal example of aone-dimensional (1D) diamond chain antiferromagnet. Early studies of thismaterial imply the presence of an ordered antiferromagnetic phase below $T_N\sim 1.9$ K while magnetization measurements have revealed a 1/3 magnetizationplateau. Until now, no corroborating neutron scattering results have beenpublished to confirm the ordered magnetic moment structure. We present recentneutron diffraction results which reveal the presence of commensurate magneticorder in azurite which coexists with significant magnetoelastic strain. Thelatter of these effects may indicate the presence of spin frustration in zeroapplied magnetic field. Muon spin rotation, $\mu$SR, reveals an onset ofshort-range order below 3K and confirms long-range order below $T_N$.