NMR Study of Mixed Crystals (CH₃NH₃)₂Cu(Cl_1-xBr_x)₄

Abstract

The spin structures in the magnetically ordered state are studied by Cu and Br NMR in the concentration region of 82%≦ x ≦97%. From the NMR spectra in zero applied field, the compound of x =82% is a ferromagnet with the moment direction parallel to the [110]-axis. In the region of \(82\%{<}x{\lesssim}97\%\), the moment direction inclines from the [110]-axis to the [001]-axis. The existence of the “oblique phase” is concluded. The weak lines suggest some distributions of the moment direction.