Title Synthesis and properties of charge-ordered thallium halide perovskites, $CsTl_{0.5}^{+}Tl_{0.5}^{3+}X_{3}$ (X = F or Cl) : theoretical precursors for superconductivity?Synthesis and properties of charge-ordered thallium halide perovskites, $CsTl_{0.5}^{+}Tl_{0.5}^{3+}X_{3}$ (X = F or Cl) : theoretical precursors for superconductivity? Author Retuerto, M. Emge, T. Hadermann, J. et al. Faculty/Department Faculty of Sciences. Physics Research group Electron microscopy for materials research (EMAT) Publication type article Publication 2013Washington, D.C., 2013 Subject Physics Chemistry Source (journal) Chemistry of materials / American Chemical Society. - Washington, D.C. Volume/pages 25(2013):20, p. 4071-4079 ISSN 0897-4756 ISI 000326209200017 Carrier E Target language English (eng) Full text (Publishers DOI) Affiliation University of Antwerp Abstract Recently, CsTlCl3 and CsTlF3 perovskites were theoretically predicted to be potential superconductors if they were optimally doped. The syntheses of these two compounds together with a complete characterization of the samples are reported. CsTlCl3 was obtained as orange crystals in two different polymorphs: a tetragonal phase (I4/m) and a cubic phase (Fm (3) over barm). CsTlF3 was formed as a light brown powder, and also as a double cubic perovskite (Fm (3) over barm). In all three CsTlX3 phases, Tl+ and Tl3+ were located in two different crystallographic positions that accommodate their different bond lengths. In CsTlCl3, some Tl vacancies were found in the Tl+ position. The charge ordering between Tl+ and Tl3+ was confirmed by X-ray absorption and Raman spectroscopy. The Raman spectroscopy of CsTlCl3 at high pressure (58 GPa) did not indicate any phase transition to a possible single Tl2+ state. However, the highly insulating material became less resistive with an increasing high pressure, while it underwent a change in its optical properties, from transparent to deeply opaque red, indicative of a decrease in the magnitude of the band gap. The theoretical design and experimental validation of the existence of CsTlF3 and CsTlCl3 cubic perovskites are the necessary first steps in confirming the theoretical prediction of superconductivity in these materials. E-info http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000326209200017&DestLinkType=RelatedRecords&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000326209200017&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000326209200017&DestLinkType=CitingArticles&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 Handle