Structural and luminescence studies of trivalent europium complexes with pentaethylene glycol and 18-crown-6 ligands in the presence of picrate anion

Muhammad I. Saleh, Eny Kusrini, Bahruddin Saad, Rohana Adnan, Abdussalam S. Mohamed, Bohari M. Yamin

Research output: Contribution to journalArticlepeer-review

15 Citations (Scopus)

Abstract

Two new isostructural complexes of europium picrate (Eu-Pic) with pentaethylene glycol (EO5) and 18-crown-6 (18C6) ligands formed complexes of molecular formula [Eu(Pic)2(18C6)]+(Pic)- I and [Eu(Pic)2(EO5)]+(Pic)- II have been isolated and characterised. Compound I showed 10-coordination number through six oxygen atoms from the 18C6 ligand and two bidentate picrate anions. Meanwhile, compound II exhibited 9-coordination number via six oxygen atoms from EO5 ligand, two oxygen atoms from a bidentate and one oxygen atom from monodentate picrate anions. Photoluminescence (PL) spectra of the solid-state europium complexes display sharp lines which are assigned to 5D07F0-4 and 5D17F1,2,4 transitions. No emission of polyether ligands is observed, indicating that the energy transfer from the polyether ligands to the Eu3+ ion is quite efficient. The PL spectra of [Eu(Pic)2(OH2)6]+(Pic)-·6H2O III, [Eu(NO3)3(OH2)3]·(18C6) IV, [Eu(NO3)3·6H2O] V and Eu2O3 VI are also observed. Compounds I-IV exhibited high Ω2 intensity parameter values, namely 16.93, 10.23, 17.10 and 12.35 (in units of 10-20 cm2), respectively. These relatively high values reflect the hypersensitive behaviour of the 5D07F2 transition and indicate that the Eu3+ ion is located in a highly polarisable chemical environment.

Original languageEnglish
Pages (from-to)871-880
Number of pages10
JournalJournal of Luminescence
Volume126
Issue number2
DOIs
Publication statusPublished - 1 Oct 2007

Keywords

  • 18-Crown-6
  • Europium
  • Pentaethylene glycol
  • Photoluminescence
  • Picrate complex

Fingerprint Dive into the research topics of 'Structural and luminescence studies of trivalent europium complexes with pentaethylene glycol and 18-crown-6 ligands in the presence of picrate anion'. Together they form a unique fingerprint.

Cite this