EPR measurements in the one-dimensional anisotropic paramagnet CsNiF3

Abstract
The EPR line has been observed in CsNiF3 at room temperature. The anisotropy of its width is analysed in terms of the dynamics associated with 4‐spin correlation functions (4‐SCf). The EPR width can be attributed unambiguously to the single‐ion coupling. We therefore get the opportunity to obtain information on specific 4‐SCf. Their dynamics is discussed in the conclusion.