Relationship between the optical properties and the structure of a new complex: Nd(III)-isothiocyanate-2,2′-bipyridine

New type of complex: [Nd(NCS)3(2,2′-bipyridine)2(H2O)] was synthesized as a crystal. It crystallizes with the space group P-1. In this complex, there are seven Nd-N coordination bonds and one Nd-O(W) bond. The absorption and emission spectra as well as the fluorescence dynamics of the above mentioned complex were studied in details. In the electronic spectra of the title complex at low temperatures, the splitting of the 4f-4f transitions indicates a single low symmetry of the Nd3+ ion in this crystal. The lower nephelauxetic parameter (β), positive bonding parameter (b1/2), and Sinha parameter (δ) indicate some covalent character of the bond between the Nd3+ and the ligands. The decay time of the 4F3/2 state of the Nd3+ ion for the title compound is small and amounts to 0.26 μs.73