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.

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The stability constants of the supramolecular complexes formed between L ((a,b,c,d)) or their Zn(2+) complexes, and adenosine 5'-triphosphate (ATP) in aqueous solution were determined by potentiometric titrations (25 degrees C, I = 0.1 mol dm(-3) KNO(3)). The results show that protonated aliphatic-substituted L (a,d) and aromatic-substituted L (b,c) ligands and/or Zn(II) ion can efficiently recognition the substrate, ATP. All of the equilibrium studies, (1)H and (31)P nuclear magnetic resonance spectra indicate that multiple interactions, including coordination, pi-stacking, ion-pairing, H-bonding, and possible ion-pi-donor, hydrophobic and even van der Waals interactions exist in the Zn(II)-L-ATP systems. On the other hand, the recognition of the substrates by the protonated ligands was significantly promoted by the addition of Zn(II), which leads to coordination competition between the mixed ligands, L and nucleotide. In Zn(II)/L/ATP systems the tendency for phosphate chain to receive proton and metal ion increases, facilitating the cleavage of the phosphate chain of the nucleotide.

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