Inclusions of the Hexagonal Phase in Cubic ZnS Ceramics

• Published in: Journal of applied spectroscopy 2019-03, Vol.86 (1), p.56-60
• Main Authors: Dunaev, А. A., Pakhomov, P. M., Khizhnyak, S. D., Chmel, A. E.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Atomic/Molecular Structure and Spectra; Ceramics; Chemical synthesis; Chemical vapor deposition; Crystal structure; Crystallites; Crystallography; Heat treating; Heterogeneous structure; Hexagonal phase; Hot isostatic pressing; Hot pressing; Inclusions; Organic chemistry; Paleontology; Phase composition; Phase transitions; Physical vapor deposition; Physics; Physics and Astronomy; Powdered metal products; Raw materials; Recrystallization; Reflectance; Spectra; Transition temperature; Wurtzite; Zinc sulfide; Zincblende
• ISSN: 0021-9037; 1573-8647
• DOI: 10.1007/s10812-019-00780-x

IR Fourier reflectance spectra (50–500 cm –1 ) of ZnS ceramics synthesized by chemical vapor deposition (including those with additional hot isostatic pressing), hot pressing, and physical vapor deposition are presented. The samples are assumed to have a cubic crystallographic structure (sphalerite) because of the phase composition of the raw materials and the temperature prehistory of them. However, a weak band at ~295 cm –1 that is characteristic of hexagonal ZnS crystals (wurtzite) manifests itself in both the reflectance spectra and the spectra of optical constants of all samples. Sphalerite → wurtzite recrystallization below the nominal phase transition temperature (1023°С) may be a consequence of the tendency ZnS to form the polytypical structure, which is facilitated in this ceramic material by the highly heterogeneous structure of the crystallites themselves.