Structural behavior, crystal chemistry, and phase transitions in substituted leucite; high-resolution neutron powder diffraction studies

Other| February 01, 1997 Structural behavior, crystal chemistry, and phase transitions in substituted leucite: High-resolution neutron powder diffraction studies David C. Palmer; David C. Palmer University of Cambridge, Department of Earth Sciences, Cambridge, United Kingdom Search for other works by this author on: GSW Google Scholar Martin T. Dove; Martin T. Dove Search for other works by this author on: GSW Google Scholar Richard M. Ibberson; Richard M. Ibberson Search for other works by this author on: GSW Google Scholar Brian M. Powell Brian M. Powell Search for other works by this author on: GSW Google Scholar American Mineralogist (1997) 82 (1-2): 16–29. https://doi.org/10.2138/am-1997-1-203 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation David C. Palmer, Martin T. Dove, Richard M. Ibberson, Brian M. Powell; Structural behavior, crystal chemistry, and phase transitions in substituted leucite: High-resolution neutron powder diffraction studies. American Mineralogist 1997;; 82 (1-2): 16–29. doi: https://doi.org/10.2138/am-1997-1-203 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentBy SocietyAmerican Mineralogist Search Advanced Search Abstract High-resolution neutron powder diffraction was used to study phase transitions in the leucite phases of KAISi2O6, RbAlSi2O6, CsAlSi2O6, and KFeSi2O6. The temperature-dependent structural behavior involves two mechanisms: relaxation of the tetrahedral framework about channel cations, and slowly changing T-O bond lengths. The high-temperature cubic phase is characterized by a fully-extended tetrahedral framework; thermal expansion occurs by an increase in mean T-O bond lengths. On decreasing temperature, a displacive phase transition to tetragonal symmetry is manifested by an optic instability; twisting of tetragonal prisms of comer-linked (Al,Si)O4 tetrahedra about [001] leads to collapse of the 〈111〉 structural channels and concomitant volume reduction. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.