A New Refinement of the Crystal Structure of MnAlF5: New Structural Correlations with MnCrF5 and Cr2F5 Using Orthogonal Subcell Twinning

✍ Scribed by Gérard Ferey; Marc Leblanc; Anne-Marie Mercier

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 441 KB
• Volume: 102
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1993.1003

✦ Synopsis

A new refinement of the crystal structure of (\mathrm{MnAlF}{5}), needed for further powder neutron diffraction studies, shows that it is centric (S.G. Cmcm, (a=3.5837(4) \AA, b=9.854(1) \AA, c=9.537) (1) (\AA, Z=) 4). The structure was refined from 720 independent refiections ( (R=0.023, R{\mathrm{w}}=0.022) ). Its crystal chemistry is basically the same as previously described, but a new comparison with (\mathrm{MnCrF}{5}) and (\mathrm{Cr}{2} \mathrm{~F}{5}) is proposed. It first shows that the latter two structures represent two different monoclinic distortions of the same structural type, despite large differences in their lattice parameters. This leads to a description of (\mathrm{MnAlF}{5}) as a twinning of two subcells of this structural type and to an introduction of the concept of subcell orthogonal twinning. O 1993 Academic Press, Inc.