Paramagnetic Resonance Absorption in Some Cr+3 Complexes

Abstract

The paramagnetic resonance absorptions in several trichelate complexes of Cr⁺³ have been investigated at room temperature and at 1.2‐ and 3.0‐cm wavelengths. From single crystal measurements on chromic acetylacetonate the orientations of the electric axes were determined and the parameters in the spin‐Hamiltonian found to be g = 1.983±0.002, |D| = 0.592±0.002 cm^—1, and |E| = 0.052±0.002 cm^—1. The asymmetric single absorption peak with g = 4 found in several of the powders and in their liquid solutions is explained on the basis of the relatively large value of D associated with the individual trichelate molecules. The apparent inadequacy of the ``ionic'' model for several chromic compounds is also discussed.