Skip to main content
SpringerLink
Log in

The Correlation Between f–f Absorption and Sensitized Visible Light Emission of Luminescent Pr(III) Complexes: Role of Solvents and Ancillary Ligands on Sensitivity

  • Original Paper
  • Published:
Journal of Fluorescence Aims and scope Submit manuscript

Abstract

The electronic absorption, excitation and sensitized visible light emission studies of three praseodymium (III) complexes: [Pr(fod)3(bpy)], [Pr(fod)3(phen)] and [Pr(fod)3(bpm)]n (fod = anion of 6,6,7,7,8,8,8- heptafluoro-2,2-dimethyl-3,5-octanedione; bpy = 2,2'-bipyridyl, phen = 1,10-phenanthroline, bpm = 2,2'-bipyrimidine) in a series of non–aqueous solvents is presented. The f–f absorption transitions of Pr(III) are environment sensitive which is reflected by the change in the intensity (oscillator strength) and band shape (stark splitting) upon change in the solvent and/or the ligands. The sensitization of intense Pr(III) emission, in the visible region, of the complexes in solution upon excitation into the ligand centered π→π* absorption band is remarkable. The planar phen has pronounced impact and increases considerably the emission intensity of Pr(III) luminescence than the flexible bpy while bpm has been found least effective in promoting the emission intensity. The intensity of the f-f absorption and sensitized emission are correlated with the nature of the solvents. The donor solvent pyridine enhances the emission intensity of the [Pr(fod)3(phen)] drastically and of [Pr(fod)3(bpy)] marginally while the luminescent intensity of [Pr(fod)3(bpm)]n is decreased. The combined photophysical studies demonstrate that entry of the solvent molecule(s) to inner coordination sphere (complex–solvent interaction) is governed by the structure and basicity of the ancillary heterocyclic ligand attached to the Pr(III) complex. The strong donor DMSO transforms the three complexes into a similar species, [Ln(fod)3(DMSO)2], which results in similar electronic absorption and emission properties of the complexes in this solvent. The results demonstrate that highly luminescent praseodymium chelates can be designed with ligands containing suitable energy levels and their emission properties can be further modulated through suitable ancillary ligands and donor solvents, thus opening perspectives for applications in electroluminescent devices and luminescent probes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Chart 1
Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

Similar content being viewed by others

References

  1. Bünzli JCG (2006) Benefiting from the unique properties of lanthanide ions. Acc Chem Res 39:53–61

    Article  PubMed  Google Scholar 

  2. Bünzli JCG, Piguet C (2005) Taking advantage of luminescent lanthanide ions. Chem Soc Rev 34:1048–1077

    Article  PubMed  Google Scholar 

  3. Werts MHV (2005) Making sense of lanthanide luminescence. Sci Prog 88:101–131

    Article  PubMed  CAS  Google Scholar 

  4. Binnemans K (2009) Lanthanide-based luminescent hybrid materials. Chem Rev 109:4283–4374

    Article  PubMed  CAS  Google Scholar 

  5. Brunet E, Olga J, Rodriguez-Ubis JC (2007) Supramolecularly organized lanthanide complexes for efficient metal excitation and luminescence as sensors in organic and biological applications. Curr Chem Biol 1:11–39

    Article  CAS  Google Scholar 

  6. Leonard JP, dos Santos CMG, Plush SE, McCabe T, Gunnlaugsson T (2007) pH driven self-assembly of a ternary lanthanide luminescence complex: the sensing of anions using a β-diketonate-Eu(III) displacement assay. Chem Commun. pp 129–131

  7. Kido J, Okamoto Y (2002) Organo lanthanide metal complexes for electroluminescent materials. Chem Rev 102:2357–2368

    Article  PubMed  CAS  Google Scholar 

  8. Latva M, Takalo H, Mukkala VM, Matachescu C, Rodríguez-Ubis JC, Kankare J (1997) Correlation between the lowest triplet state energy level of the ligand and lanthanide(III) luminescence quantum yield. J Lumin 75:149–169

    Article  CAS  Google Scholar 

  9. Sabatini N, Guardigli M, Lehn JM (1993) Luminescent lanthanide complexes as photochemical supramolecular devices. Coord Chem Rev 123:201–228

    Article  Google Scholar 

  10. Binnemans K (2005) Rare-earth beta-diketonates. In: Gschneidner KA Jr, Bünzli JCG, Pecharsky VK (eds) Handbook on the physics and chemistry of rare earths, vol 35. Elsevier, Amsterdam, pp 107–272

    Google Scholar 

  11. Bassett AP, Magennis SW, Glover PB, Lewis DJ, Spencer N, Parsons S, Williams RM, Cola LD, Pikramenou Z (2004) Highly luminescent, triple- and quadruple-stranded, dinuclear Eu, Nd, and Sm(III) lanthanide complexes based on bis-diketonate ligands. J Am Chem Soc 126:9413–9424

    Article  PubMed  CAS  Google Scholar 

  12. Belluci A, Barberio G, Crispini A, Ghedini M, Deda ML, Pucci D (2005) Synthesis and luminescent properties of novel lanthanide(III) β-diketone complexes with nitrogen p, p’-disubstituted aromatic ligands. Inorg Chem 44:1818–1825

    Article  Google Scholar 

  13. Ha-Thi MH, Delaire JA, Michelete V, Leray I (2010) Sensitized emission of luminescent lanthanide complexes based on a phosphane oxide derivative. J Phys Chem A 114:3264–3269

    Article  PubMed  CAS  Google Scholar 

  14. Anasri AA, Singh N, Khan AF, Singh SP, Iftikhar K (2007) Solvent effect on optical properties of hydrated lanthanide tris-acetylacetone. J Lumin 127:446–452

    Article  Google Scholar 

  15. Voloshin AI, Shavaleev NM, Kazakov VP (2001) Luminescence of praseodymium (III) chelates from two excited states (3P0 and 1D2) and its dependence on ligand triplet state energy. J Lumin 93:199–204

    Article  CAS  Google Scholar 

  16. Regulacio MD, Pablico MH, Vasquez JA, Myers PN, Gentry S, Prushan M, Tam-Chang S-W, Stoll SL (2008) Luminescence of Ln(III) dithiocarbamate complexes (Ln = La, Pr, Sm, Eu, Gd, Tb, Dy). Inorg Chem 47:1512–1523

    Article  PubMed  CAS  Google Scholar 

  17. Yu J, Zhang H, Fu L, Deng R, Zhou L, Li H, Liu F, Fu H (2003) Synthesis, structure and luminescent properties of a new praseodymium(III) complex with β-diketone. Inorg Chem Commun 6:852–854

    Article  CAS  Google Scholar 

  18. Yan B, Wang W-J, Song Y-S (2006) Double fluorescence conversion in ultraviolet and visible region for some praseodymium complexes of aromatic carboxyates. J Fluoresc 16:495–500

    Article  PubMed  CAS  Google Scholar 

  19. Ishii A, Kishi S, Ohtsu H, Iimori T, Nakabayashi T, Ohta N, Tamai N, Melnik M, Hasegawa M, Shigesato Y (2007) Molecular distortion effect on ff-emission in a Pr(III) complex with 4, 7-diphenyl-1, 10-phenanthroline. ChemPhysChem 8:1345–1351

    Article  PubMed  CAS  Google Scholar 

  20. Ahmed Z, Iftikhar K (2010) Solution studies of Lanthanide(III) complexes based on 1,1,1,5,5,5-hexafluoro-2,4-pentanedione and 1,10-phenanthroline Part−I. Synthesis, 1 H NMR, 4f-4f absorption and photoluminescence. Inorg Chim Acta 363:2606–2615

    Google Scholar 

  21. Irfanullah M, Iftikhar K (2009) New dinuclear lanthanide(III) complexes based on 6, 6, 7, 7, 8, 8, 8-heptafluoro-2, 2-dimethyl-3, 5-octanedione and 2, 2′-bipyrimidine. Inorg Chem Commun 12:296–299

    Article  CAS  Google Scholar 

  22. Irfanullah M, Iftikhar K (2010) New hetero-dilanthanide complexes containing Ln1(fod)3 and Ln2(fod)3 fragments (Ln = Pr-Nd; Nd-Sm; Eu-Tb and Ho-Er) linked by bis-diimine bridging ligand. Inorg Chem Commun 13:694–698

    Article  CAS  Google Scholar 

  23. Irfanullah M, Iftikhar K (2010) Pyrazine-bridged dinuclear complex formation by early lanthanides (LaIII, PrIII, NdIII and SmIII) containing bulky fluorinated β-diketonates. Inorg Chem Commun 13: 1234–1238

    Google Scholar 

  24. Irfanullah M, Iftikhar K (2010) Photoluminescence, optical absorption and hypersensitivity in mono- and dinuclear Lanthanide (TbIII and HoIII) β-diketonate complexes with diimines and bis-diimine bridging ligand. J Lumin 130:1983–1993

    Google Scholar 

  25. Irfanullah M, Iftikhar K (2010) Hypersensitivity in the luminescence and 4f–4f absorption properties of mono- and dinuclear EuIII and ErIII complexes based on fluorinated β-diketone and diimine/bis-diimine ligands. J Flouresc. doi:10.1007/s10895-010-0691-4

    Google Scholar 

  26. Iftikhar K, Sayeed M, Ahmad N (1982) Mixed-ligand complexes of trivalent lanthanide ions with.beta.-diketones and heterocyclic amines. Inorg Chem 21:80–84

    Article  CAS  Google Scholar 

  27. Springer CS Jr, Meek DW, Sievers RE (1967) Rare earth chelates of 1, 1, 1, 2, 2, 3, 3-heptafluoro-7, 7-dimethyl-4, 6-octanedione. Inorg Chem 6:1105–1110

    Article  CAS  Google Scholar 

  28. Sayeed M, Ahmad N (1981) Mixed ligand complexes of trivalent lanthanide ions with β-diketones and heterocyclic amines and their use as possible shift reagents. J Inorg Nucl Chem 43:3197–3202

    Article  CAS  Google Scholar 

  29. van Staveren DR, van Albada GA, Haasnoot JG, Kooijman H, Lanfredi AMM, Nieuwenhuizen PJ, Spek AL, Ugozzoli F, Weyhermüller T, Reedijk J (2001) Increase in coordination number of lanthanide complexes with 2, 2′-bipyridine and 1, 10-phenanthroline by using β-diketonates with electron-withdrawing groups. Inorg Chim Acta 315:163–171

    Article  Google Scholar 

  30. Julve M, Verdaguer M, Munno GD, Real JA, Bruno G (1993) Synthesis, crystal structure, and magnetic properties of (.mu.-bipyrimidine)(cyanato)copper(II) and -(thiocyanato)copper(II) complexes. Inorg Chem 32:795–802

    Article  CAS  Google Scholar 

  31. van Albada GA, Smeets WJJ, Spek AL, Reedijk J (1998) The crystal structure and IR spectra of μ-(bipyrimidine-N1, N1′, N5, N5′)-bis[(azido-N1)(methanol)(bipyrimidine-N1, N1′)copper(II)] bis(triflate) bis(methanol). J Chem Crystallogr 28:427–432

    Article  Google Scholar 

  32. Zucchi G, Maury O, Thuéry P, Ephritikhine M (2008) Structural diversity in neodymium bipyrimidine compounds with near infrared luminescence: from mono- and binuclear complexes to metal-organic frameworks. Inorg Chem 47:10398–10406

    Article  PubMed  CAS  Google Scholar 

  33. Fratini A, Swavey S (2007) Luminescent and structural properties of a Eu(III) complex: Formation of a one-dimensional array bridged by 2, 2′-bipyrimidine. Inorg Chem Commun 10:636–638

    Article  CAS  Google Scholar 

  34. Fratini A, Richards G, Larder E, Swavey S (2008) Neodymium, gadolinium, and terbium complexes containing hexafluoroacetylacetonate and 2, 2'-bipyrimidine: structural and spectroscopic characterization. Inorg Chem 47:1030–1036

    Article  PubMed  CAS  Google Scholar 

  35. Eliseeva SV, Kotova OV, Gumy F, Semenov SN, Kessler VG, Lepnev LS, Bünzli JCG, Kuzmina NP (2008) Role of the ancillary ligand N, N-dimethylaminoethanol in the sensitization of EuIII and TbIII luminescence in dimeric β-diketonates. J Phys Chem A 112:3614–3226

    Article  PubMed  CAS  Google Scholar 

  36. Iftikhar K (1996) Mixed-ligand lanthanide complexes-IX NMR spectral study of the adducts of Ln(fod)3 with 2, 2′-bipyridyl and 1, 10-phenanthroline. Polyhedron 15:1113–1120

    Article  CAS  Google Scholar 

  37. Crosswhite HH, Dieke GH, Carter WJ (1965) Free-ion and crystalline spectra of Pr3+ (Pr IV). J Chem Phys 43:2047–2054

    Article  CAS  Google Scholar 

  38. Sugar J (1965) Energy levels of Pr3+ in the vapor state. Phys Rev Lett 14:731–732

    Article  CAS  Google Scholar 

  39. Carnall WT, Fields PR, Rajnak K (1968) Spectral intensities of the trivalent lanthanides and actinides in solution II. Pm3+, Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, and Ho3+. J Chem Phys 49:4424–4442

    Article  CAS  Google Scholar 

  40. Judd BR (1962) Optical absorption intensities of rare-earth ions. Phys Rev 127:750–761

    Article  CAS  Google Scholar 

  41. Ofelt GS (1962) Intensities of crystal spectra of rare–earth ions. J Chem Phys 37:511–520

    Article  CAS  Google Scholar 

  42. Peacock RD (1975) The intensities of lanthanide f ↔f transitions. Struct Bond 22:83–122

    Article  CAS  Google Scholar 

  43. Khan AA, Iftikhar K (1997) Mixed-ligand lanthanide complexes—XI. Absorption spectra and hypersensitivity in the complexes of PrIII, NdIII, HoIII and ErIII in nonaqueous solutions. Polyhedron 16:4153–4161

    Article  CAS  Google Scholar 

  44. Ansari AA, Irfanullah M, Iftikhar K (2007) Optical absorption and NMR spectroscopic studies on paramagnetic neodymium(III) complexes with β-diketone and heterocyclic amines: the environment effect on 4f–4f hypersensitive transitions. Spectrochim Acta A 67:1178–1188

    Article  CAS  Google Scholar 

  45. Ansari AA, Ahmed Z, Iftikhar K (2007) Nuclear magnetic resonance and optical absorption spectroscopic studies on paramagnetic praseodymium(III) complexes with β-diketone and heterocyclic amines. Spectrochim Acta A 68:176–183

    Article  CAS  Google Scholar 

  46. Khan AA, Saxena AK, Iftikhar K (1997) Mixed-ligand lanthanide complexes—X. Interaction of trivalent lanthanides with 1, 10-phenanthroline and thiocyanate in alcohol. Polyhedron 16:4143–4152

    Article  CAS  Google Scholar 

  47. Hasegawa Y, Si T, Yoshida T, Kawai H, Kawai T (2008) Enhanced deep-red luminescence of tris(hexafluoroacetylacetonato)samarium(III) complex with phenanthroline in solution by control of ligand coordination. J Phys Chem A 112:803–807

    Article  PubMed  CAS  Google Scholar 

  48. Khan AA, Iftikhar K (1994) Mixed-ligand lanthanide complexes—VII. Complexes of 1, 10-phenanthroline and thiocyanate. Polyhedron 4:3199–3208

    Article  Google Scholar 

  49. Khan AA, Hussain HA, Iftikhar K (2003) 4f–4f absorption spectra of nine-coordinate Pr (III) and Nd (III) complexes in different environments. Spectrochim Acta A 59:1051–1059

    Article  Google Scholar 

  50. Hussain HA, Iftikhar K (2003) 4f–4f hypersensitivity in the absorption spectra and NMR studies on paramagnetic lanthanide chloride complexes with 1, 10-phenanthroline in non-aqueous solutions. Spectrochim Acta A 59:1061–1074

    Article  CAS  Google Scholar 

  51. Misra SN, Mehta SB (1992) Ligand mediated pseudohypersensitivity of some 4f-4f transitions (3 H4→3P2, 3P1, 3P0 and 1D2) and coordination environment around praseodymium (III). Ind J Pure Appl Phys 30:159–164

    CAS  Google Scholar 

  52. Misra SN, Joshi GK, Singh M (1981) Study of some anhydrous praseodymium fluoro β-diketonates interelectronic repulsion, spin-orbit interaction bonding electronic energy levels and IR spectra. J Inorg Nucl Chem 43:206–208

    Article  CAS  Google Scholar 

  53. Misra SN, Devi MI (1997) The synthesis and determination of the octacoordinated structure of Pr(III) and Nd(III) complexes with β-diketones and diols in non aqueous solutions: evidence of some participation of π-electron density of diols with Pr(III) and Nd(III) in complexation. Spectrochim Acta A 53:1941–1946

    Article  Google Scholar 

  54. Correa-Ascencio M, Galván-Miranda EK, Rascón-Cruz F, Jiménez-Sandoval O, Jiménez-Sandoval SJ, Cea-Olivares R, Jancik V, Toscano RA, García-Montalvo V (2010) Lanthanide(III) complexes with 4, 5-bis(diphenylphosphinoyl)-1, 2, 3-triazolate and the use of 1, 10-phenanthroline as auxiliary ligand. Inorg Chem 49:4109–4116

    Article  PubMed  CAS  Google Scholar 

  55. Hemmilä I, Laitala V (2005) Progress in lanthanides as luminescent probes. J Fluoresc 15:529–542

    Article  PubMed  Google Scholar 

  56. Hemmilä I, Mukkala VM, Takalo H (1995) Effect of C–H bonds on the quenching of luminescent lanthanide chelates. J Fluoresc 5:159–163

    Article  Google Scholar 

  57. Huang Y-L, Huang M-Y, Chan T-H, Chang B-C, Lii K-H (2007) Synthesis, structural characterization, and luminescence properties of lanthanide oxalatophosphonates: Na[M3(H2O)4(C2O4)4(CH3PO3)]·2H2O (M = Nd and Pr). Chem Mater 19:3232–3237

    Article  CAS  Google Scholar 

Download references

Acknowledgments

MI thanks CSIR (Govt. of India) for a Senior Research Fellowship.

Author information

Authors and Affiliations

  1. Department of Chemistry, Jamia Millia Islamia, New Delhi, 110 025, India

    Mir Irfanullah & Khalid Iftikhar

Authors
  1. Mir Irfanullah
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Khalid Iftikhar
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Khalid Iftikhar.

Additional information

This research was supported, in part, by the UGC Special Assistance Programme of the Department of Chemistry, Jamia Millia Islamia (No. F.540/17/DRS/2007/SAP-1).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Irfanullah, M., Iftikhar, K. The Correlation Between f–f Absorption and Sensitized Visible Light Emission of Luminescent Pr(III) Complexes: Role of Solvents and Ancillary Ligands on Sensitivity. J Fluoresc 21, 673–686 (2011). https://doi.org/10.1007/s10895-010-0755-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10895-010-0755-5

Keywords

Search

Navigation