Exploring the role of neutral ligands in modulating the photoluminescence of samarium complexes with 1,1,1,5,5,5‐hexafluoro‐2,4‐pentanedione

Abstract

Four eight‐coordinated luminescent samarium complexes of type [Sm(hfpd)3L2] and [Sm(hfpd)3L′] [where hfpd = 1,1,1,5,5,5‐Hexafluoro‐2,4‐pentanedione L = tri‐octyl‐phosphine oxide (TOPO) and L′ = 1,10‐phenanthroline (phen), neocuproine (neoc) and bathocuproine (bathoc) were synthesized via a stoichiometrically controlled approach. This allows for precise control over the stoichiometry of the complexes, leading to reproducible properties. This investigation focuses on understanding the impact of secondary ligands on the luminescent properties of these complexes. Infrared (IR) spectra provided information about the molecular structures, whereas 1H and 13C nuclear magnetic resonance (NMR) spectra confirmed these structural details along with the coordination of ligands to trivalent Sm ion. The UV–vis spectra revealed the molar absorption coefficient and absorption bands associated with the hfpd ligand and photoluminescence (PL) spectroscopy demonstrated intense orange‐red emission (648 nm relative to 4G5/2 → 6H9/2) from the complexes. The Commission Internationale de l'Éclairage (CIE) triangles indicated that the complexes emitted warm orange red light with color coordinates (x, y) ranging from (0.62, 0.36) to (0.40, 0.27). The investigation of the band gap as well as color parameters confirms the utility of these complexes in displays and LEDs.

Optimizing white light emission in Dy(iii) complexes: impact of energy transfer from mono and bidentate ligands on luminescence

“…Similarly, free TOPO exhibits a peak at 1210 cm −1 ascribed to P O that is shifted towards 1204 cm −1 in Dy1. 35 Moreover, the complexes exhibit low-intensity peaks around 425–428 cm −1 , associated with Dy–O modes and at ∼546 cm −1 , attributed to Dy–N coordination in Dy2–Dy4 complexes. 36 Such changes in spectrum suggest that Dy( iii ) ion not only coordinates with carbonyl oxygen of hfpd but also directly interacts with two nitrogen atoms of phen and its derivatives in Dy2–Dy4 and two oxygen atoms of TOPO in Dy1 complex.…”