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Abstract: Zeolite losod prepared with tetrabutylammonium hydroxide was applied as matrix for sulfur anion-radicals thermally generated from precursors (elemental sulfur and alkalis or alkaline oligosulfides). We hoped that large los cages could favor formation and stabilization of big radicals (e.g. red ). The products with maintained LOS structure, however, always showed light green or blue coloration (due to and radicals) and bigger radicals never were detected (EPR). It is likely that the sulfur radicals in the products occupy rather eri cages in LOS structure, whereas the large los cages do not accommodate any radicals, because several of them could stay there and subsequently recombine to ordinary oligosulfides. Some reduction of los cage size by means of Cs or K cations resulted in a degradation of LOS structure. Introduction of sulfur compounds already during the losod crystallization disturbed formation of LOS structure. [Copyright &y& Elsevier]

Abstract: Colored products have been obtained by thermal treatment of erionite mixed with elemental sulfur and alkalis (Na2CO3 or K2CO3). Synthesis at lower temperature (500°C) resulted in forming colored materials with preserved ERI structure (particularly with potassium cations), whereas the treatment of highly alkaline mixtures at high temperature (800°C) caused re-crystallization to SOD (when Na was used) or to unknown structures (with K). The ESR spectra of the products with preserved original ERI structure recorded at room temperature show two signals, one with g =2.030 and another with g tensor value either 2.045 (for sodium containing samples) or 2.005 (for the potassium bearing products). The latter signal could be considered as a reflection of radicals immobilized in small ε-cages, but it is more likely that it presents anisotropic component of the radical spectrum. The spectra measured at 77K show anisotropy indicating three values of orthorhombic g-tensor, which is typical of radical, although the values vary for particular samples. [Copyright &y& Elsevier]

Abstract: The colored products analogous to ultramarine have been obtained by thermal treatment (500–800°C) of cancrinite mixed with elemental sulfur and alkalis. The samples obtained at 500°C maintain the original structure of cancrinite, while heating of the mixture at 800°C resulted in zeolite structure transformation towards SOD in the case of mixture containing Na+ cations and to kaliophilite or unknown structures, when K+ or Li+ were applied as alkali sources. Encapsulation of sulfur species inside the cancrinite cages does not result in the generation of another radicals but , which is reflected in the ESR spectra resembling those embedded in sodalite cages. [Copyright &y& Elsevier]

Abstract: MOF-5 and ZIF-8 were used for the first time as matrices for pigments containing entrapped dmit. The chromophore was introduced either by impregnation or by its synthesis from CS2 inside the matrices. Pigments with ZIF-8 resisted washing and maintained the structure, while these with MOF-5 underwent structure altering or amorphization. [Copyright &y& Elsevier]