Photometric study and spectral characterization of samarium-tris-β-carboxylate complexes with heterocyclic auxiliary moieties

Abstract

The orange light emanating Samarium complexes are synthesized, by using β-keto carboxylic acid (L) as the prime ligand and four auxiliary ligands: bathophenanthroline, 2,2′-bipyridyl, 1,10-phenanthroline and 4,4′-dimethyl-2,2′-bipyridyl. Elemental analysis is used to assess the elemental content of prepared compounds, Whereas the bonding evidence between metal and the primary and secondary sensitizers is ascertained by examining the FT-IR, NMR and UV-visible spectra. The luminescent parameters such as excitation, emission and decay time are determined by stimulating the complexes at λ_max=353 nm. The bright orange emitting hue of the complex is attributable to the intense peak at 566nm, 602nm and 650nm due to the transition from ⁴G_5/2 to ⁶H_5/2, ⁶H_7/2 and ⁶H_9/2 respectively. Synthesized complexes show exceptional thermal stability which demonstrates their potential applications in military radars and solar devices. The crystalline nature of the synthesized complex is examined via XRD analysis which indicate that the particles lie in the nano range. The optoelectronic characteristics like refractive index and optical band gap also reflect the applicability of these complexes in photonic devices and wide-gap semiconductors. Furthermore, the colorimetric properties like CIE 1931 color coordinates, Correlated color temperature (CCT value ˂ 3000 K) and Exquisite color purity show conformance with the warm reddish-orange light coordinates provided by "The National Television System Committee and also validate their use as marvelous emitters in electroluminescent, display, OLEDs (organic light emitting diodes) and laser materials.