Molecular structure and paramagnetic properties of Tris-diisobutyl- dithiophosphinate complexes of europium(III) with 2,2′-Bipyridyl in solution using NMR

Tris-diisobutyl-dithiophosphinate complexes of europium(III) with 2,2′-Bipyridyl are of great interest as promising luminescent sensors for biology and medicine. ¹H and ¹³C NMR measurements are reported for the CDCl ₃ solution of [Eu(2,2′-Bipy)(i-DBDTPh) ₃] complex. The analysis of the structural parameters found by relaxation spectroscopy NMR testifies that the bipyridyl and i-DBDTPh anions are in the first coordination sphere of a Ln cation. The found experimental results indicate that the structure of these complexes in solution is similar to that one in the solid state (known from the X-ray crystal structure data). Paramagnetic complex investigated in the paper represents the new type of thermometric NMR sensors and lanthanide paramagnetic probes for in situ temperature control in solution.