New KRb2Sb4BO13 and Rb3Sb4BO13 compounds prepared by Rb+/K+ ion exchange from the K3Sb4BO13 ion conductorCCDC 1870994-1870996. For crystallographic data in CIF or other electronic format see DOI: 10.1039/c8ce01712c

• Main Authors: Doux, Jean-Marie, Stephant, Nicolas, La Salle, Annie Le Gal, Joubert, Olivier, Guyomard, Dominique, Quarez, Eric
• Format: Article
• ISSN: 1466-8033
• DOI: 10.1039/c8ce01712c

The crystal structures of new K 3− x Rb x Sb 4 BO 13 compounds ( x = 2, 3), prepared via ion exchange from K 3 Sb 4 BO 13 , are reported. They adopt the triclinic crystal system and exhibit a localized Rb/K disorder at room temperature. The crystal structures were determined from single-crystal X-ray diffraction at T = 25 °C for both end-members of the family, leading to a reinvestigation of the K 3 Sb 4 BO 13 crystal structure, and one intermediate composition KRb 2 Sb 4 BO 13 . The structure consists of hexagonal Sb 3 O 9 bronze-like layers alternately separated by edge-sharing Sb 2 O 10 dimers and BO 3 triangles, forming interconnected tunnels filled by Rb + /K + ions. The differences between the structures are based on the Rb/K disorder inside the tunnels conferring an advanced view of the cation diffusion paths. Additional information about conduction pathways was provided by the bond valence energy landscape (BVEL) method. Conduction pathways of Rb + /K + ions in new ion conductors K 3− x Rb x Sb 4 BO 13 (0 ≤ x ≤ 3).