Next Article in Journal
Crystallization, Structure Determination and Reticular Twinning in Iron(III) Salicylate: Fe[(HSal)(Sal)(H2O)2]
Next Article in Special Issue
Determination of the Correct Composition of “Hydrous Lead(II) Oxotellurate(IV)” as PbTeO3, Crystallizing as a New Polymorph
Previous Article in Journal
Thermal Stability of Epitaxial Graphene Electrodes for Conductive Polymer Nanofiber Devices
Open AccessArticle

Influence of Alkali Metal Substitution on the Phase Transition Behavior of CsGaQ2 (Q = S, Se)

1
Institut für Anorganische Chemie, Universität Regensburg, Universitätsstraße 31, 93040 Regensburg, Germany
2
Deutsches Elektronensynchrotron (DESY), Notkestraße 85, 22607 Hamburg, Germany
*
Author to whom correspondence should be addressed.
Academic Editor: Helmut Cölfen
Crystals 2017, 7(12), 379; https://doi.org/10.3390/cryst7120379
Received: 20 October 2017 / Revised: 27 November 2017 / Accepted: 4 December 2017 / Published: 14 December 2017
(This article belongs to the Special Issue Synthesis and Structural Investigations of Polymorphic Compounds)
The formation of solid solution series Cs1−xMxGaQ2-mC64 (M = K, Rb; Q = S, Se; x = 0–1) was studied by X-ray diffraction and spectroscopic methods, revealing a complete miscibility of CsGaQ2-mC64 with RbGaQ2 and KGaSe2, and a large miscibility gap with KGaS2. All solid solution members exhibit similar Raman spectra, indicating the covalent Ga-Q bonding character. The similar optical band gaps likewise further contribute to this conclusion. Up to a certain degree of substitution, these solid solutions undergo a phase transition similar to CsGaQ2-mC64. The influence of the substitution parameter x on phase transition process was investigated in situ using high-temperature X-ray powder diffraction experiments. Phase-pure solid solutions of the high-temperature polymorphs Cs1−xMxGaQ2-mC16 were obtained up to xmax(K) = 0.1 and xmax(Rb) = 0.3. The crystal structures of these new CsGaQ2-mC16 analogous high-temperature phases were refined from synchrotron diffraction data by Rietveld-refinement. View Full-Text
Keywords: chalcogenogallates; polymorphism; solid solutions; in situ X-ray diffraction; synchrotron radiation; Rietveld refinement chalcogenogallates; polymorphism; solid solutions; in situ X-ray diffraction; synchrotron radiation; Rietveld refinement
Show Figures

Graphical abstract

MDPI and ACS Style

Friedrich, D.; Schlosser, M.; Etter, M.; Pfitzner, A. Influence of Alkali Metal Substitution on the Phase Transition Behavior of CsGaQ2 (Q = S, Se). Crystals 2017, 7, 379.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop