High-Field Magnetization of One-DimensionalS=1/2 Trimer System 3CuCl2·2dioxane

Abstract
The high-field magnetization process of a one-dimensional S =1/2 trimer system, 3CuCl 2 ·2dioxane, is studied on powder samples using a pulse magnet up to 30 T between 1.5 K and 9 K. The magnetization increases nonlinearly and saturates around 15 T, characteristic of low-dimensional Heisenberg antiferromagnets. The magnetization data are consistent with a previously proposed model in which ferromagnetic trimers composed of three S =1/2 spins are weakly coupled antiferromagnetically to form a S =3/2 antiferromagnetic chain. Based on this model, the antiferromagnetic intertrimer interaction is directly derived as J AF =-16.2 K. However, the observed magnetization curve suggests that a composite spin system consisting of three S =1/2 spins has more of a quantum nature than does a genuine S =3/2 system, because the ferromagnetic intratrimer interaction is not sufficiently strong.