Monometallic Ln3+ and heterometallic Ln3+–Cd2+complexes based on pentafluorophenylacetic acid: efficient control of dimension and luminescent properties†.

Four new complexes [Ln(pfaa)3(H2O)2] n (Ln = Eu (1), Tb (2)) and [Ln2Cd2(pfaa)10 (phen)2(EtOH)2]·2MeCN (Ln = Eu (3), Tb (4), phen = 1,10-phenanthroline) based on pentaphorphenylacetic acid (Hpfaa) have been prepared and completely investigated. The structures of compounds 1 and 3 were studied by single crystal X-ray diffraction analysis: the isostructural complexes 1 and 2 represent 1D coordination polymer, while the isostructural complexes 3 and 4 are molecular compounds. Complexes 1–4 show strong lanthanide-centred luminescence, since the introduction of phenanthroline leads to a significant increase in the observed lifetime (τ obs) and photoluminescent quantum yield. New complexes of Eu3+ and Tb3+ with pentafluorophenylacetic acid have been studied. During synthesis under hydrothermal conditions, polymer structures are formed, while the introduction of phenanthroline and Cd2+ makes it possible to obtain molecular complexes. A change in the structure leads to significant changes in the luminescent properties. [ABSTRACT FROM AUTHOR]