Silver and gold luminescent metallomesogens based on pyrazole ligands

Dalton Trans. 2008 Dec 28:(48):6912-24. doi: 10.1039/b808487d. Epub 2008 Nov 3.

Abstract

A series of ionic bis(pyrazole)-silver(I) and -gold(I) complexes [ML(2)][A] (M = Ag, Au; A = BF(4)(-), PF(6)(-), NO(3)(-)), prepared by coordination of the mesomorphic L = Hpz(2R(n)) or non-mesomorphic L = Hpz(R(n)) pyrazole ligands (Hpz(2R(n)) = 3,5-bis(4-alkyloxyphenyl)pyrazole; Hpz(R(n)) = 3-(4-alkyloxyphenyl)pyrazole), has been studied. The complexes exhibit enantiotropic behaviour, showing smectic A (SmA) mesophases. The choice of the ligands allows the achievement of 'H' or 'U' molecular shapes, which appear to be responsible for the attainment of liquid crystal mesophases, these not being dependent on the coordinating or non-coordinating nature of the A counteranions. The new complexes are photoluminescent both in the solid state and in solution at room temperature. In addition, the luminescent behaviour of selected compounds as a function of the temperature indicates that the luminescence is maintained in the mesophase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Crystallography, X-Ray
  • Gold / chemistry*
  • Ligands
  • Liquid Crystals / chemistry*
  • Luminescence*
  • Organometallic Compounds / chemical synthesis
  • Organometallic Compounds / chemistry*
  • Pyrazoles / chemistry*
  • Silver / chemistry*
  • Spectrometry, Fluorescence
  • Temperature

Substances

  • Ligands
  • Organometallic Compounds
  • Pyrazoles
  • Silver
  • pyrazole
  • Gold