TY - JOUR

T1 - Elucidating structural order and disorder phenomena in mullite-type Al4B2O9 by automated electron diffraction tomography

AU - Zhao, Haishuang

AU - Krysiak, Yaşar

AU - Hoffmann, Kristin

AU - Barton, Bastian

AU - Molina-Luna, Leopoldo

AU - Neder, Reinhard B.

AU - Kleebe, Hans Joachim

AU - Gesing, Thorsten M.

AU - Schneider, Hartmut

AU - Fischer, Reinhard X.

AU - Kolb, Ute

N1 - Funding information: Haishuang Zhao gratefully acknowledges the financial support from the Carl-Zeiss-Stiftung. Ya?ar Krysiak is grateful for the financial support by the Stipendienstiftung Rheinland-Pfalz. Thorsten M. Gesing and Reinhard X. Fischer gratefully thank the Deutsche Forschungsgemeinschaft for the financial support (GE1981/5-1 and FI442/19-1). The JEM-ARM200F was partially funded by the Deutsche Forschungsgemeinschaft (DFG/INST163/2951).

PY - 2017/5/1

Y1 - 2017/5/1

N2 - The crystal structure and disorder phenomena of Al4B2O9, an aluminum borate from the mullite-type family, were studied using automated diffraction tomography (ADT), a recently established method for collection and analysis of electron diffraction data. Al4B2O9, prepared by sol-gel approach, crystallizes in the monoclinic space group C2/m. The ab initio structure determination based on three-dimensional electron diffraction data from single ordered crystals reveals that edge-connected AlO6 octahedra expanding along the b axis constitute the backbone. The ordered structure (A) was confirmed by TEM and HAADF-STEM images. Furthermore, disordered crystals with diffuse scattering along the b axis are observed. Analysis of the modulation pattern implies a mean superstructure (AAB) with a threefold b axis, where B corresponds to an A layer shifted by ½a and ½c. Diffraction patterns simulated for the AAB sequence including additional stacking disorder are in good agreement with experimental electron diffraction patterns.

AB - The crystal structure and disorder phenomena of Al4B2O9, an aluminum borate from the mullite-type family, were studied using automated diffraction tomography (ADT), a recently established method for collection and analysis of electron diffraction data. Al4B2O9, prepared by sol-gel approach, crystallizes in the monoclinic space group C2/m. The ab initio structure determination based on three-dimensional electron diffraction data from single ordered crystals reveals that edge-connected AlO6 octahedra expanding along the b axis constitute the backbone. The ordered structure (A) was confirmed by TEM and HAADF-STEM images. Furthermore, disordered crystals with diffuse scattering along the b axis are observed. Analysis of the modulation pattern implies a mean superstructure (AAB) with a threefold b axis, where B corresponds to an A layer shifted by ½a and ½c. Diffraction patterns simulated for the AAB sequence including additional stacking disorder are in good agreement with experimental electron diffraction patterns.

KW - Aluminum borate

KW - Crystal structure determination

KW - Disorder

KW - Electron diffraction

KW - Superstructure

UR - http://www.scopus.com/inward/record.url?scp=85014120419&partnerID=8YFLogxK

U2 - 10.1016/j.jssc.2017.02.023

DO - 10.1016/j.jssc.2017.02.023

M3 - Article

AN - SCOPUS:85014120419

VL - 249

SP - 114

EP - 123

JO - Journal of solid state chemistry

JF - Journal of solid state chemistry

SN - 0022-4596

ER -