Solid meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS(4))-chitosan supramolecular complexes were prepared by addition of porphyrin to an aqueous solution of chitosan at pH values. The precipitates obtained were assigned as 1 (pH 6.8) and 2 (pH 2.5) and characterized by spectroscopic, thermal, and microscopic methods. Spectroscopic investigation confirmed the presence of TPPS(4) and chitosan in both products and that the porphyrin is highly self-associated. H-type (stacked) of TPPS(4) aggregation was proposed for 1 and J-type (tilted) for 2. Thermal analysis revealed different pyrolysis routes of the complexes depending on their structural diversity. Light microscopic analysis indicated fibrous and lamellar microstructures, respectively, for 1 and 2. SEM and AFM analysis showed that both complexes consist of compact nanostructures; their size and interconnection is different for 1 and 2. Based on structural inferences, self-assembling hierarchy models were proposed for both of the TPPS(4)-chitosan supramolecular complexes.

The thermal decomposition and infrared spectrum of sabugalite were studied. The infrared spectrum was interpreted on the basis of site and factor symmetry analysis and correlated with the X-ray powder diffraction data. The dehydration of sabugalite is characterized by three endotherms. The anhydrous phase decomposes at 440-680 ~ On the basis of the infrared spectrum in Nujol, oxonium ions are postulated in the structure of sabugalite. The infrared spectrum in a KBr disk is probably influenced by the sample preparation mode. Sabugalite does not form a meta I hydrate. Its first new partly dehydrated phase is isostructural with metaautunite II. Sabugalite, HAI(

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Línekite, K 2 Ca 3 [(UO 2 )(CO 3 ) 3 ] 2 .8H 2 O, is a new uranyl tricarbonate mineral from Jáchymov, Western Bohemia, Czech Republic. It occurs in association with grimselite, andersonite, liebigite, čejkaite, schröckingerite, agricolaite, ježekite and braunerite. Línekite forms from uranium-rich aqueous solutions and its origin is associated with post-mining processes. Línekite is orthorhombic, space group Pnnm, with a = 17.0069(5) Å, b = 18.0273(5) Å, c = 18.3374(5) Å and V = 5622.1(2) Å 3 , and Z = 8. It forms tabular, mostly isometric crystals, up to c. 0.5 mm across, typically in multiple intergrowths. The color is pale olive to khaki green and it has a greenish white to yellowish white streak. Crystals are transparent and have vitreous luster. The Mohs hardness is estimated to be between 2 and 3. Línekite is brittle with an uneven fracture and perfect cleavage on {100} and very good cleavage on {010}. It exhibits intense greenish yellow luminescence under both short-(254 nm) and long-wave (366 nm) UV radiation. The calculated density is 2.922 g/cm 3 . The mineral is biaxial (+) with indices of refraction, α = 1.546(2), β = 1.550, γ = 1.562(2). The 2V obs is moderate; the calculated 2V is +60°. Optical orientation: 12 and 4.053 (204) 15. The structure of línekite was refined from single-crystal X-ray data to R = 0.034 for 4468 unique observed reflections (I obs > 3σI). The structure consists of prominent (Ca(H 2 O) 2 [(UO 2 )(CO 3 ) 3 ]) 2-layers parallel to (100), which define a square grid, leading to a strong tetragonal pseudosymmetry of línekite. Between the layers, disordered K + cations and H 2 O molecules are localized. The structure is closely related to other uranyl tricarbonate minerals, e.g., albrechtschraufite and andersonite, due to the presence of a very characteristic paddle-wheel motif, Ca[(UO 2 )(CO 3 ) 3 ] 4 Ca.