Synthesis, X-ray crystal structure and determination of non-covalent interactions through Hirshfeld surface analysis of a pure red emitting asymmetrical octacoordinated Sm(III) complex

A new organo-samarium complex [Sm(tfac)₃(DPEPO)] (Sm1) has been synthesized by incorporating trifluoroacetylacetone (tfac) as the primary antenna ligand and bis(2-(diphenylphosphino)phenyl)ether oxide (DPEPO) as the ancillary ligand. The structure of the complex was established by single crystal X-ray diffraction (SC-XRD) analysis, which shows that the coordination sphere is composed of a EuO₆O₂ core (octacoordinated). Continuous shape measures (CShMs) further revealed that the geometry around Sm(III) is trigonal dodecahedral with approximate D_2d-symmetry. Different non-covalent interactions (NCIs) and their % contribution to the supramolecular structure and their role in stabilizing the structure were determined by Hirshfeld surface analysis. Photophysical properties of the complex were determined in the solid-state and in DCM solution. The complex emits brilliant red emission in the solid-state and in DCM solution with excited state lifetime in microsecond regime and relative quantum yield of 2.5±10 % in solution.