Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.334, 405-414, 1999
Magnetic properties of the single crystals of layered Cu(II) and Co(II) complexes with 3-imidazoline nitroxides
Single crystals of Cu(II) and Co(II) complexes with stable nitroxides 4-(2-ethoxycarbonyl-2'-oxoethylidene)-2,2,5,5-tetramethyl-3-imidazoline-1-oxyl (HL1) and 4-(2-methoxycarbonyl-2'-oxoethylidene)-2,2,5,5-tetramethyl-3-imidazoline-1-oxyl (HL2) have been investigated by the static magnetic susceptibility method. It was found that bulk ferromagnetic ordering is inherent in layered CuL2I and alpha -CuL22, at similar to 5 K. Easy magnetization axes were determined for both compounds. At the same time, the complex beta -CuL22, possessing a molecular structure, does not show noticeable anisotropy in the region 2-300 K. For the layered complex CoL21, the magnetic transition temperature, if any, is lower than 2 K. In the whole range 2-300 K, the single crystals of CoL21 show a rather high anisotropy of magnetic susceptibility.