Synthesis, characterization, and near-infrared photoluminescence of novel neodymium(III) complexes

A series of monoporphyrinate neodymium(III) complexes stabilized by the anionic tripodal ligand hydridotris(pyrazol-1-yl)borate were prepared and characterized. These complexes were characterized by elemental analysis and spectroscopy. The structure of resulting complex was determined by single-crystal X-ray diffraction. The complex crystallized in the monoclinic space group P2₁, with a 13.7347(11), b 27.156(2), c 15.5397(13) Å, β 114.1490(10)°, and V 5288.8(7)ų. The neodymium(III) ion is coordinated by four nitrogen atoms from the porphyrinate dianion and three nitrogen atoms from the anionic tripodal ligand. Photoluminescence studies showed that the porphyrinate dianion absorbed light and transferred energy to the Nd³⁺ centre, a process which then allowed the metal ion to emit efficiently at 885, 900, and 1071 nm. The effects of the substituent and the solvent on emission efficiency were also investigated.