ИСТИНА

The majority of modern single ion magnets represents complexes of d- and f-metal ions with volume organic ligands and only numerous SIMs are based on paramagnetic ions distributed in diamagnetic solid state matrix. However such solid state inorganic matrixes could provide some advantages as chemical and thermal stability as well as possibility to manipulate with crystal field and chemical environment of magnetic ions by operations with a matrix. In this work a new cobalt based single ion magnet representing paramagnetic ions distributed in a diamagnetic apatite matrix was synthesized: compounds with nominal composition Ca5(PO4)3(CoO2)x(OH)1-2x (x from the range 0 – 0.3). It was showed that Ueff for the calcium and early searched strontium samples are practically equal but nevertheless slow magnetic relaxation in the calcium samples changes significantly: only one type of relaxing magnetic centers is observed whereas we have found two different types of magnetic centers with substantially different energy barriers in the strontium analogues.