Thiophene‐containing organometallic polymers studied by near‐edge x‐ray absorption spectroscopy

A near-edge x-ray absorption fine structure (NEXAFS) spectroscopy investigation on the electronic structure of some novel π-conjugated organometallic polymers is presented. The investigated materials consist of Pt and Pd(II) complex units linked together through σ-bonded organic spacers of ethynyl-thiophene type in a polymeric array. The C K-edge NEXAFS spectra were interpreted by comparison with literature data and with the spectra of reference samples. The linking between the thiophene rings and alkyne groups produces a splitting of the C1s → π* peak observed in the spectra of the thiophene systems. Angle-dependent measurements, performed at normal and grazing incidence of the linearly polarized photons, evidenced a preferential orientation of the polymer chains with an average tilt angle of 45° for the thiophene moieties.

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