Influence of a series of pyridine ligands on the structure and photophysical properties of Cd(II) complexes

Among the group 12 metal ions, the Cd(II) ion presents an ionic radius comparable to that of Hg(II), while its electronegativity resembles that of Zn(II). Thus, these characteristics make it a suitable candidate for the synthesis of fluorescent coordination complexes given that it tends to maximize...

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Detalles Bibliográficos
Autores: Ejarque, Daniel, Calvet Pallàs, Maria Teresa, Font Bardia, Ma. Mercedes, Pons, Josefina
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2022
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/208825
Acceso en línea:https://hdl.handle.net/2445/208825
Access Level:acceso abierto
Palabra clave:Cristalls
Cristal·lografia
Estructura cristal·lina (Sòlids)
Crystals
Crystallography
Layer structure (Solids)
Descripción
Sumario:Among the group 12 metal ions, the Cd(II) ion presents an ionic radius comparable to that of Hg(II), while its electronegativity resembles that of Zn(II). Thus, these characteristics make it a suitable candidate for the synthesis of fluorescent coordination complexes given that it tends to maximize the chelation enhanced effect (CHEF), while its electronegativity helps to prevent the quenching of fluorescence generated by the heavy atom effect. Accordingly, herein, we performed a systematic study using Cd(II) compounds bearing α-acetamidocinnamic acid (HACA) and different N-, N^N- and N^N^N-pyridine ligands (dPy), namely pyridine (py) (1), 3-phenylpyridine (3-phpy) (2), 2,2′-bipyridine (2,2′-bipy) (3), 1,10-phenantroline (1,10-phen) (4) and 2,2′:6′,2′′-terpyridine (terpy) (5). The elucidation of their crystal structures revealed the formation of one coordination polymer (1), one dimer (3) and three monomers (2, 4, and 5). All the synthesized compounds were characterized via analytical and spectroscopic techniques, and their molecular and supramolecular structures were discussed. The photophysical properties of 1–5 in MeOH were studied and their quantum yields (Φ) were calculated, revealing an enhancement in the Φ value of the complexes generated by the CHEF of dPy.