Magnetic ordering processes in the quasi-one-dimensional metamagnets RbFeCl3⋅2aq and CsFeCl3⋅2aq (aq=H2O,D2O)

The static and dynamic properties of the quasi-one-dimensional canted Ising antiferromagnets RbFeCl3·2aq and CsFeCl3·2aq (aq=H2O,D2O) are investigated in the ordered phases by neutron diffraction and magnetization measurements. For 2 K¿T¿3 K the magnetic behavior in varying field H may be explained by a sequence of collective reversals of all moments in separate long-range-ordered chains, each chain reversal being initiated by a thermally excited moment reversal at one of the chain ends. The behavior at low T is characterized by nonexponential relaxation towards a partly disordered array of long-range-ordered chains. The properties for 4.2