STUDY OF THE STRUCTURE AND PARAMAGNETIC PROPERTIES OF THE [Dy(H 2 O) n (CyDTA)] – COMPLEX IN AN AQUEOUS SOLUTION USING NMR DATA

The structure and paramagnetic properties of the [Dy(H 2 O) n (CyDTA)] – complex are studied by 1 H NMR using the analysis of paramagnetic shifts and spin-spin relaxation rates for an ab initio structural model. It is shown that significant temperature-dependent spectral line broadening is due to the Curie-spin contribution to the paramagnetic spin-spin relaxation rate enhancement. The complex demonstrates conformational, kinetic, and thermodynamic stability in the temperature range from 278 K to 368 K. The maximum temperature sensitivity of chemical shifts d (δ exp )/ dT is equal to 0.44 ppm/K. Due to its thermodynamic and conformational stability, this compound may be prospective for the design of thermally sensitive NMR probes in aqueous media.