Chlorine NMR in CsNiCl3 and CsCuCl3

Abstract

The analysis of 35Cl NMR measurements in single crystals of CsNiCl3 and CsCuCl3 at room temperature yielded the quadrupole coupling and magnetic shift tensors at the chlorine positions. For the two inequivalent sites in CsCuCl3 the following parameters were found: v35= 11.249 Mc/sec, η = 0.389 (general position), and v35q = 10.701 Mc/sec, η = 0.131 (special position), and for CsNiCl3: v35q = 8.349 Mc/sec, η = 0.387. The calculated hyperfine constants along and perpendicular to the metal–chlorine bonds are in CsCuCl3: A‖ = 21.3, A⊥ = 3.0 (Clgen) and A‖ = 17.7, A⊥ = 3.9 (Clspec) and in CsNiCl3: A‖ = 8.0, A⊥ = 2.4 (all in units 10−4 cm−1). The hyperfine constants are compared to MO calculations. The 63Cu and 65Cu NMR has been observed and partially analyzed.