Neptunium(V) Perrhenate Complex with 1,10-Phenanthroline [(NpO2)(ReO4)(Phen)(H2O)2]: Crystal Structure and Absorption Spectra

Neptunium(V) perrhenate complex [(NpO2)(ReO4)(Phen)(H2O)2] was synthesized with 1,10-phenanthroline as a ligand. Its composition and structure were determined by X-ray diffraction analysis. The coordination polyhedron of the Np atom is a pentagonal bipyramid. The nearest surrounding of the neptunoyl ion includes the oxygen atom of the ReO4 anion, two nitrogen atoms of phenanthroline, and the oxygen atoms of two water molecules. The crystals of the compound are monoclinic. The main crystallographic parameters are the following: space group P21/c, unit cell parameters a = 7.288(1) Å, b = 10.513(2) Å, c = 20.936(4) Å, β = 96.939(5)°, Z = 4, V = 1592.2(5) Å3. Absorption spectra of the compound in visible and IR regions are reported.