97567-29-8Relevant academic research and scientific papers
Photostudies of (+), (+), and (+) in Solution and in Rigid, Low-Temperature Glasses. Simultaneous Multiple Emissions from Intraligand and Charge-Transfer States
Rader, Rosemary A.,McMillin, David R.,Buckner, Michael T.,Matthews, Thomas G.,Casadonte, Dominick J.,et al.
, p. 5906 - 5912 (1981)
Spectral studies of a series of complexes of the type (+) have been carried out where biL denotes 2,2'-bipyridine, 1,10-phenanthroline, and 2,9-dimethyl-1,10-phenanthroline which will be abbreviated as bpy, phen, and dmp, respectively.The dmp complex, unlike the others, emits fairly efficiently in fluid solution and has been studied in detail.All three complexes exhibit metal-to-ligand charge transfer (d-?*) transitions in solution around 360 nm, but solutions of the dmp complex give an extra visible absorption band which is attributable to a second copper complex formed according to the equilibrium: (+) = (+) + 2PPh3.This dissociation of PPh3 is readily suppressed by the addition of excess PPh3, and under these conditions, the E1/2 of the complex is estimated to be ca. 0.7 V vs.SCE.Under the same conditions, the complex has an emission lifetime of 330 ns and an emission quantum yield of 1.4E-3.PPh3 is not a quencher, but both electron-transfer and energy-transfer quenching have been observed.The reduction potential of the excited complex is estimated to be ca. -0.9 V vs.SCE.In rigid glasses at low temperature all three complexes exhibit broad, structureless emissions with lifetimes in the microsecond domain which can be assigned to 3d-?* states.Additional components with lifetimes in the millisecond domain have been observed for the phen and dmp complexes.The latter have characteristic vibronic structures which enable us to assign them as 3?-?* emissions involving the coordinated heterocyclic ligands.The occurrence of multiple emissions from these systems is rationalized in terms of current models from the literature.Finally, weak sub-nanosecond components have been time resolved from the total emission spectra of the phen and bpy complexes, and possible origins for these components are discussed.
Synthesis and study on a series of phosphorescent Cu(I) complexes having sterically blocking ligands
Zhang, Kai,Zhang, Dong
, p. 341 - 348 (2014/03/21)
In this paper, we report six phosphorescent Cu(I) complexes with 1,10-phenanthroline-derived ligands and phosphorous ligands, including their synthesis, crystal structures, photophysical properties, and electronic nature. The Cu(I) center has a distorted tetrahedral geometry within the Cu(I) complexes. Theoretical calculation reveals that all emissions originate from triplet metal-to-ligand-charge-transfer excited state. It is found that the introduction of alkyl moieties into 2,9-positions of 1,10-phenanthroline is highly effective on restricting the geometric relaxation that occurs in excited states, which greatly enhances the photoluminescence (PL) performances, including PL quantum yield improvement, PL decay lifetime increase, and emission blue shift.
