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Rapid reactions of tetra(tert-butyl)phthalocyanine, H₂(tbpc), and its zinc complex, [Zn(tbpc)], with tellurium tetrachloride (TeCl₄) in non-aqueous solutions have been investigated. Upon mixing respective solutions containing the reactants, drastic spectral changes occurred in chloroform and toluene even at room temperature. The electronic spectra of the products indicated that the reactions involved an acid-base equilibrium where the phthalocyanines and tellurium tetrachloride acted as a Lewis base and a Lewis acid respectively. By monitoring the spectral changes based on various initial molar ratios of the reactants, the compositions of the products for each system have been determined. [Zn(tbpc)] formed a 1:1 (tbpc:TeCl₄) adduct in both chloroform and toluene, showing the same spectra close to those of the known monoprotonated phthalocyanines. On the other hand, H₂(tbpc) formed a 1:1 adduct in chloroform but a 1:3 adduct in toluene even though both products showed essentially the same spectra close to those of the known diprotonated phthalocyanines. Equilibrium constants have been calculated for the four systems. Magnetic circular dichroism (MCD) spectra of conjugated acids of phthalocyanines have been studied for the first time.

The normal states of simple elemental metal and complex compound superconductors have been studied by using first principle methods and model analysis. The flat/steep band electronic structure and the peak-like structure of electron-phonon coupling have been found as two universal characteristics. A new Hamiltonian is proposed to describe the electronic structure of insulating solids.

Knowledge of distribution coefficient values is essential in estimating the refining efficiency, and plays an important role during the purification process, typically zone refining. The effective distribution coefficient "K_eff" of impurities Se, Fe, Cr and Pb in tellurium was determined in the present study and found to be 0.48, 0.05, 0.25 and 0.19, respectively. The results are validated by comparing with the available published data, and we observed a difference of less than one order, which was reasonably comparable. The influence of "K_eff" on zone refining efficiency was examined and it was noticed that the effective distribution coefficient increases with respect to the translation rate, which is minimum at an optimum lower translation rate (= 30 mm/h). The relative solute concentration C/C₀ is determined experimentally, which shows the best fit of experimental values with Pfann's equation. The impurity profile along the length of the zone refined ingot is also discussed.

Recent advances in the chemistry of main group porphyrin complexes are surveyed. New, unprecedented structural types for porphyrin complexes which have been revealed from the recent reports of boron and tellurium porphyrins are described. Advances in the preparation and reactivity of Group 14 (silicon and tin) and Group 15 porphyrin complexes are discussed. A systematic variation in the out-of-plane distortion (ruffling) of light element Group 14 and 15 porphyrin complexes has become apparent now that a significant number of structurally characterized examples are at hand.

An expanded heterocorrole, meso-tetraaryl-tellura[22]porphyrin(6.1.1.0), containing a bipyrrole moiety and a six-carbon long link, has been synthesized. The reaction path proceeds through a controlled acid-promoted extrusion of one tellurium atom from meso-aryl-26,28-ditellurasapphyrin, leading to a structure where one tellurophene ring of the substrate is replaced by a bridging acyclic four-carbon unit. This aromatic porphyrin-annulene hybrid is conformationally flexible in solution, on account of the C₄ unit adopting two different configurations: trans–cis–trans or all-trans. Studies of the dynamic behavior of tellura[22]porphyrin(6.1.1.0) in solution were performed by means of ¹H and ¹²⁵Te NMR spectroscopy. The X-ray structure of the all-trans form with trapezoid macrocyclic skeleton is also presented.

An expanded heterocorrole, meso-tetraaryl-tellura[22]porphyrin(6.1.1.0), containing a bipyrrole moiety and a six-carbon long link, has been synthesized. The reaction path proceeds through a controlled acid-promoted extrusion of one tellurium atom from meso-aryl-26,28-ditellurasapphyrin, leading to a structure where one tellurophene ring of the substrate is replaced by a bridging acyclic four-carbon unit. This aromatic porphyrin-annulene hybrid is conformationally flexible in solution, on account of the C4 unit adopting two different configurations: trans–cis–trans or all-trans. Studies of the dynamic behavior of tellura[22]porphyrin(6.1.1.0) in solution were performed by means of ¹H and ¹²⁵Te NMR spectroscopy. The X-ray structure of the all-trans form with trapezoid macrocyclic skeleton is also presented.