“…F À , O 2À or H À . Cs 4 Mg 3 F 10 (Steinfink & Brunton, 1969) is also used to identify the aristotype structure, with further examples, such as Ba 4 Ir 3 O 10 (Wilkens & Mü ller-Buschbaum, 1991), Ba 4 (Ir,Al) 3 O 10 (Mü ller-Buschbaum & Neubacher, 1990;Neubacher & Mü ller-Buschbaum, 1991), Cs 4 M 0 3 F 10 (M 0 = Co, Ni or Zn; Schmidt et al, 1992), Ba 4 Ru 3 O 10 (Dussarrat et al, 1996;Carim et al, 2000), Sr 4 Mn 3 O 10 (Floros et al, 2000) and Cs 4 Mg 3 H 10 (Bertheville et al, 2002), illustrating the range of this structure type. A related structure is exemplified by Cs 4 Cu 3 F 10 , in which linear tricopper segments of face-sharing CuF 6 octahedra are likewise bridged through corner-sharing to two other segments at each end, but in a stepwise fashion so that the terminal ligands on neighboring corner-shared CuF 6 octahedra are trans, rather than cis as in the Cs 4 Mg 3 F 10 -type structures (Kissel & Hoppe, 1988;Dussarrat et al, 1995).…”