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Inverse electron demand Diels-Alder (IEDDA) reaction has been employed as a powerful ligation in several fields. In the current work, a synthetic approach relying on IEDDA reaction is developed for preparation of a porphyrin based covalent organic polymer (PoTz-COP). A tetra-norbornene functional porphyrin is chosen as the core and a bis-tetrazine as the linker. The PoTz-COP is readily formed by just mixing the components without a catalyst and under mild conditions. Chemical structure, morphology (XRD, SEM-EDX), porosity (BET), thermal stability (TGA), optical and gas sorption (CO2 uptake) and selectivity (CO2/N2) properties via Myers and Prausnitz's ideal adsorbed solution theory (IAST) are investigated. PoTz-COP shows remarkably high adsorption selectivity of CO2 over N2 as found 80, 42, and 47 at 50/50 ratio; 84, 39 and 40 at 15/85 ratio; and 84, 39 and 38 at 05/95 ratio at temperatures of 273 K, 298 K and 320 K at 1.1 bar pressure respectively. The optical band gap is determined relatively narrow as 1.66 eV.

International audience; In this work, the synthesis and the nonlinear absorption and population dynamics investigation of a series of zinc phthalocyanines (ZnPcs) dissolved in chloroform are reported. In order to determine the relevant spectroscopic parameters, such as absorption cross-sections of singlet and triplet excited states, fluorescence relaxation times, intersystem crossing, radiative decay and internal conversion, different optical and spectroscopic techniques were used. By single pulse and pulse train Z-scan techniques, respectively, singlet and triplet excited states‘ absorption cross-section were determined at 532 nm. Furthermore, the intersystem crossing time was obtained by using both techniques combined with the fluorescence lifetime determined by time-resolved fluorescence. The radiative and internal conversion rates were determined from the fluorescence quantum yield of the samples. Such spectroscopy parameters are fundamental for selecting photosensitizers used in photodynamic therapy, as well as for many other applications.

The concept of octupolar molecules has considerably enlarged the engineering of second-order nonlinear optical materials by giving access to 2D and 3D architectures. However, if the archetype of octupolar symmetry is a cube with alternating donor and acceptor groups at the corners, no translation of this ideal structure into a real molecule has been realized to date. This may be achieved by designing a bis(phthalocyaninato)lutetium(III) double-decker complex with a crosswise ABAB phthalocyanine bearing alternating electron-donor and electron-acceptor groups. In this communication, we present the first step toward this goal with the synthesis, crystal structure determination, and measurement of the molecular first-order hyperpolarizability beta by harmonic light diffusion, of an original lutetium(III) sandwich complex displaying the required ABAB-type alternation for one face of the cube. This structure is characterized by an intense absorption in the near-IR due to an intervalence transition and exhibits the highest quadratic hyperpolarizability ever reported for an octupolar molecule, root )(HLS)(1907) = 5750 X 10(-30) esu.