Synthesis and photophysical properties of kinetically stable complexes containing a lanthanide ion and a transition metal antenna group

Abstract

A series of bimetallic complexes has been prepared in which an octadentate DOTA-monoamide pocket containing a bound lanthanide ion is linked covalently to a Re(I) or Ru(II) bipyridyl unit via an alkyl spacer group. The transition metal chromophores incorporated in this way act as effective sensitisers for lanthanide-centred luminescence. The rate and efficiency of energy transfer are dependent upon the nature of the spacer group, and upon the nature of the lanthanide acceptor. For the RuNd diad, there is a long rise-time associated with the energy-transfer step, such that energy transfer is rate determining in H(2)O, but not in D(2)O. The results also lead us to suggest that energy transfer may precede formation of the (3)M((Ru/Re))L((bpy))CT state and may be a competitive deactivation pathway for the precursor state ((1)M((Ru/Re))L((bpy))CT).

Ultrafast Time-Resolved Hard X-Ray Emission Spectroscopy on a Tabletop

“…One area of interest involves systems where optical signatures that interrogate the metal center directly are weak. In this context, we can point to emissive lanthanide ion species whose photophysics can be exploited in sensing, lighting, and laser technologies [54][55][56][57][58]. Within such systems, phosphorescence involves radially contracted 4f-electron metal-centered states.…”

pH‐Responsive Luminescent Lanthanide‐Functionalized Gold Nanoparticles with “On–Off” Ytterbium Switchable Near‐Infrared Emission

“…[5] However, since f-f transitions are characterized by oscillator strengths that are too weak to yield an efficient excitation path, [6] it is necessary to populate their excited state through sensitizing antennae. [10] However, to the best of our knowledge, the unique combination of AuNPs and NIR-emitting lanthanides has not yet been explored to date. [8] Moreover, unlike the sensitization of ions such as Eu III and Tb III , the excited states of the NIR lanthanides can be populated by using visibly absorbing antennae, such as organic chromophores [9] or d-metal complexes.…”

Triheterometallic Lanthanide Complexes Prepared from Kinetically Inert Lanthanide Building Blocks

“…We have previously demonstrated the molecular building block approach to preparing large lanthanide(III)‐containing architectures , , , , , , . In this study, we used the three lanthanide(III) complexes Ln ·3 , Ln ·4 and Yb ·5 , itself prepared from Yb ·6 (shown in Scheme ) as building blocks . The syntheses of the mononuclear lanthanide(III) complexes, the two DOTA monoamide complexes and the triazolyl‐DO3A complex have been reported previously , , , .…”