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Sulfur pigments synthesized from zeolite LTA under vacuum and in Air. XRD and spectroscopic (UV−vis, FTIR, Raman, ESR, ESE) characterization / Stanisław K. Hoffmann in Industrial & engineering chemistry research, Vol. 49 N° 17 (Septembre 1, 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 17 (Septembre 1, 2010) . - pp 8192–8199 Titre : Sulfur pigments synthesized from zeolite LTA under vacuum and in Air. XRD and spectroscopic (UV−vis, FTIR, Raman, ESR, ESE) characterization Type de document : texte imprimé Auteurs : Stanisław K. Hoffmann, Auteur ; Janina Goslar, Auteur ; Stefan Lijewski, Auteur Année de publication : 2010 Article en page(s) : pp 8192–8199 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Sulfur  Zeolite  Spectroscopic. Résumé : X-ray, UV−vis, FT-infrared, Raman, continuous wave, and pulsed ESR spectroscopy were applied to characterize pigments prepared at 500 °C under vacuum or in air from mixtures of zeolite A (LTA) with sulfur (40 wt %) and anhydrous sodium sulfide (Na2/S = 0.1−0.4). The samples maintained the LTA structure. Sample color results from an S3− absorption band and the shoulder of a UV band. The fingerprint and asymmetric stretch region of the IR spectra show that the pigments synthesized in air have more disordered structures. The S2−/S3−ratio was estimated from Raman spectra. The ESR spectra of S3− radicals show the existence of several phases visible as five different ESR components. Two components dominate: ideal [Na4S3−]3+ clusters and clusters existing in a disordered environment. The samples synthesized in air show a substantial distortion of local structure. Synthesis in vacuum leads to products containing about 20% of the ordered crystalline phase. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100983m [article] Sulfur pigments synthesized from zeolite LTA under vacuum and in Air. XRD and spectroscopic (UV−vis, FTIR, Raman, ESR, ESE) characterization [texte imprimé] / Stanisław K. Hoffmann, Auteur ; Janina Goslar, Auteur ; Stefan Lijewski, Auteur . - 2010 . - pp 8192–8199. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 17 (Septembre 1, 2010) . - pp 8192–8199 Mots-clés : Sulfur  Zeolite  Spectroscopic. Résumé : X-ray, UV−vis, FT-infrared, Raman, continuous wave, and pulsed ESR spectroscopy were applied to characterize pigments prepared at 500 °C under vacuum or in air from mixtures of zeolite A (LTA) with sulfur (40 wt %) and anhydrous sodium sulfide (Na2/S = 0.1−0.4). The samples maintained the LTA structure. Sample color results from an S3− absorption band and the shoulder of a UV band. The fingerprint and asymmetric stretch region of the IR spectra show that the pigments synthesized in air have more disordered structures. The S2−/S3−ratio was estimated from Raman spectra. The ESR spectra of S3− radicals show the existence of several phases visible as five different ESR components. Two components dominate: ideal [Na4S3−]3+ clusters and clusters existing in a disordered environment. The samples synthesized in air show a substantial distortion of local structure. Synthesis in vacuum leads to products containing about 20% of the ordered crystalline phase. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100983m