A series of soluble and thermally stable group 10 platinum(II) polyyne polymers of the type [-CtC-Pt(PBu 3 ) 2 -CtC-Ar-Ox-Ar-] n (where Ox = 1,3,4-oxadiazole; Ar = p-C 6 H 4 or 2,7-dihexyl-9,9fluorene) and [-CtC-Pt(PBu 3 ) 2 -CtC-Ar-Ox-Ar-Ox-Ar-] n (where Ar = 2,7-dihexyl-9,9-fluorene) along with their corresponding dinuclear model compounds [Ph-Pt(PEt 3 ) 2 -CtC-Ar-] 2 -Ox-(where Ar = p-C 6 H 4 or 2,7-dihexyl-9,9-fluorene) and [Ph-Pt(PEt 3 ) 2 -CtC-Ar-Ox-] 2 -Ar-(where Ar = 2,7dihexyl-9,9-fluorene) were prepared and characterized. The regiochemical structure of the polymers has been ascertained by single-crystal X-ray analysis on the model compoundThe photophysical properties (absorption, excitation, emission, and nanosecond transient absorption spectra) of these metalated compounds in 2MeTHF at 298 and 77 K are reported. These findings are correlated by density functional theory (DFT) calculations. Geometry optimizations predict totally planar molecules for these metalated complexes and polymers, allowing better π-conjugation across the main chain. The ligands are strongly fluorescent but become also phosphorescent when the Pt atom is introduced in the backbone of the conjugated organometallic complexes and polymers. These emissions are assigned to ππ* transitions in all cases involving the Pt d xy orbitals. These Pt compounds exhibit two-photon absorption (2PA), and their 2PA cross sections (σ 2 ) have been determined. The potential of exploiting such metallopolymers for the design of electrophosphorescent polymer light-emitting devices (PLEDs) and their use as single-dopant for white PLEDs have also been discussed.

The preparation and characterization of two d 9 -d 9 M 2 -bonded Pt 2 (dppm) 2 (CtCC 6 H 4 -M(P)) 2 complexes (where M = Zn or Pd, and P = diethylhexamethylporphyrin) were achieved. The central [Pt 2 (dppm) 2 (CtCC 6 H 4 ) 2 ] organometallic unit appears to be an independent chromophore and is suspected to be luminescent at 77 K (in 2MeTHF) in the porphyrin-containing complexes, as this is the case for the unfunctionalized Pt 2 (dppm) 2 (CtCPh) 2 parent compound. However, when this spacer is connected (by a single C-C bond) to either M(P) (M = Zn, Pd), even in the absence of conjugation (as the computed dihedral angle between the C 6 H 4 and porphyrin planes is ∼84.5°), total quenching of the luminescence of the [Pt 2 (dppm) 2 (CtCC 6 H 4 ) 2 ] central unit is observed. Only T 1 -T n absorption bands of the metalloporphyrins are observed in the nanosecond transient absorption spectra, indicating the absence of a charge-separated state in these systems, thus indicating the presence of T 1 species only. Consequently, efficient T 1 energy transfers from [Pt 2 (dppm) 2 -(CtCC 6 H 4 ) 2 ] donor to the M(P) acceptor occur. Using a lower limit of measurable value of Φ e < 0.0001, the rate for T 1 energy transfers is estimated to be >10 8 s -1 . This rate indicates a fast process, which is 4 orders of magnitude larger than as recently reported in electrostatically held dyads between the unsaturated clusters M 3 (dppm) 3 (CO) 2þ (M = Pd, Pt) and metalloporphyrins (M 0 (TPP-CO 2 -); M 0 = Zn, Pd; TPP = tetraphenylporphyrin) as the donor and acceptor, respectively (

The triplet k(ET) for three organometallic polymers built upon the diethynyl[2.2]paracyclophane was studied to show good excited state electronic communication across the materials.