Please use this identifier to cite or link to this item:
http://hdl.handle.net/2445/106554
Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | Sabalisck, Nanci Prado | - |
dc.contributor.author | Guzmán-Afonso, Candelaria | - |
dc.contributor.author | González-Silgo, Cristina | - |
dc.contributor.author | Torres, Manuel Eulalio | - |
dc.contributor.author | Pasán, J. | - |
dc.contributor.author | Castillo, J. de | - |
dc.contributor.author | Ramos-Hernández, D. | - |
dc.contributor.author | Hernández-Suarez, A. | - |
dc.contributor.author | Mestres i Vila, Ma. Lourdes | - |
dc.date.accessioned | 2017-02-06T15:55:36Z | - |
dc.date.available | 2017-02-06T15:55:36Z | - |
dc.date.issued | 2017 | - |
dc.identifier.issn | 2052-5192 | - |
dc.identifier.uri | http://hdl.handle.net/2445/106554 | - |
dc.description.abstract | In order to clarify the polymorphism in the lithium sulfate family, LiREx(NH4)1 - xSO4 (0.5 [less-than or equal to] x [less-than or equal to] 4.0 mol%, nominal value; RE = Er3+, Yb3+ and Dy3+) crystals were grown from aqueous solution by slow evaporation between 298 and 313 K. The doping of the samples allowed us to obtain two polymorphic forms, [alpha] and [beta], of LiNH4SO4 (LAS). By means of X-ray diffraction (XRD) in single crystals, we determined the crystal structures of two new [alpha]-polytypes, which we have named [alpha]1- and [alpha]2-LAS. They present the same space group P21/c and the following relation among their lattice parameters: a2 = -c1, b2 = -b1, c2 = -2a1 - c1. In order to evaluate the stability of the new [alpha]-polytypes, we performed thermal analysis, X-ray diffraction and dielectric spectroscopy on single crystals and polycrystalline samples over the cyclic temperature range: 190 [rightwards arrow] 575 [rightwards arrow] 190 K. The results obtained by all the techniques used in this study demonstrate that [alpha]-polytypes are stable across a wide range of temperatures and they show an irreversible phase transition to the paraelectric [beta]-phase above 500 K. In addition, a comparative study of [alpha]- and [beta]-polytypes shows that both polymorphic structures have a common axis, with a possible intergrowth that facilitates their coexistence and promotes the reconstructive [alpha] [rightwards arrow] [beta] transition. This intergrowth was related to small anomalies detected between 240 and 260 K, in crystals with an [alpha]-habit. | - |
dc.format.extent | 12 p. | - |
dc.format.mimetype | application/pdf | - |
dc.language.iso | eng | - |
dc.publisher | International Union of Crystallography | - |
dc.relation.isformatof | Reproducció del document publicat a: https://doi.org/10.1107/S2052520616019028 | - |
dc.relation.ispartof | Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials, 2017, vol. B73, p. 122-133 | - |
dc.relation.uri | https://doi.org/10.1107/S2052520616019028 | - |
dc.rights | (c) International Union of Crystallography, 2017 | - |
dc.source | Articles publicats en revistes (Química Inorgànica i Orgànica) | - |
dc.subject.classification | Sulfats | - |
dc.subject.classification | Liti | - |
dc.subject.classification | Polimorfisme (Cristal·lografia) | - |
dc.subject.other | Sulfates | - |
dc.subject.other | Lithium | - |
dc.subject.other | Polymorphism (Crystallography) | - |
dc.title | Structures and thermal stability of the [alpha]-LiNH4SO4 polytypes doped with Er3+ and Yb3+ | - |
dc.type | info:eu-repo/semantics/article | - |
dc.type | info:eu-repo/semantics/publishedVersion | - |
dc.identifier.idgrec | 659130 | - |
dc.date.updated | 2017-02-06T15:55:36Z | - |
dc.rights.accessRights | info:eu-repo/semantics/openAccess | - |
Appears in Collections: | Articles publicats en revistes (Química Inorgànica i Orgànica) |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
659130.pdf | 1.95 MB | Adobe PDF | View/Open |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.