EPR linewidths in an unusual copper chloride chain system

The EPR linewidths in (CH₃)₂CHNH₃]₂CuCl₄ have been measured at 78 K. The salt contains two types of structurally and magnetically inequivalent chains. Each chain can be visuallized as a narrow ribbon cut from the two dimensional (RNH₃)₂CuCl₄ structures. The EPR g values are consistent with the structural characteristics of each chain. The linewidths are influenced by anisotropic and antisymmetric exchange, and also exhibit low dimensional spin diffusion behavior. The symmetry axis of the diffusional behavior is normal to the plane of the ribbon, implying that the spin correlations in the ribbons are two dimensional in nature.