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A π-extended bis-porphyrin bridged via a diketopyrrolopyrrole unit was prepared in 5 steps. This fully conjugated π-system displays strongly distorted linear absorption, while its two-photon absorption cross-section reaches 2500-3000 GM at 940 nm. LC-like behaviour, easy orientation and low viscosity are, according to XRD, POM and DSC measurements, due to formation of plastic rather than a liquid crystal.

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We have synthesized citric-acid-stabilized magnetic nanoparticles with very good magnetization behavior and relatively low contribution from shape and surface magnetic anisotropies. In this work, we report also on a simple adsorption of doxorubicin onto the surface of these nanoferrites that can provide a facile preparation process for potential drug carriers. To estimate the amount of adsorbed doxorubicin, we propose a novel method utilizing a ternary system for the determination of interactions between drug and citric-acid-stabilized nanoparticles. The Gibbs free enthalpy of adsorption was determined from Henry's isotherm that represents the drug adsorption profile within the studied concentration range. The estimated value seems to be promising for the preparation of drug-loaded nanoparticles solely by means of the adsorption process. Additional encapsulation of doxorubicin-loaded nanoparticles in an inert polypyrrole microvessel might provide a protective surrounding for drug molecules. In our opinion, understanding the physical interactions between doxorubicin and nanoparticles might be a key factor governing drug release and overall pharmacodynamics.

The enthalpy of seven polymorphs of AgF 2 has been scrutinized up to 50 GPa using density functional theory (DFT) calculations. We show that α-Ag II F 2 (Pbca, with its puckered-sheet structure and an elongated octahedral 4 + 2 coordination of Ag) transforms above 15 GPa into a layered polymorph δ (Abma). The Jahn-Teller effect persists and the coordination of Ag(II) is of the 4 + 4 type; the Ag-FAg bridges are bent. Cubic γ structure of the CaF 2 type (Fm3m), and its Pa3 variant (η), rutile (ζ), and tetragonal 'infinite chain' P4mm structure related to AgFBF 4 (ε) are not preferred in the entire pressure window that was investigated. Electronic structure of high-pressure δ-Ag II F 2 form shows features that are characteristic for two-dimensional (2D) materials, a prerequisite for high-T C superconductivity. Our calculations also suggest that experimentally observed hightemperature β-AgF 2 (I mcm, disproportionated, i.e. a charge-density-wave form, Ag I Ag III F 4) is indeed metastable; it is slightly endothermic compared to α-Ag II F 2. This contribution is dedicated to Professor Andrzej Sadlej, eminent Polish quantum chemist, on the occassion of his 65th birthday