Bugaris Daniel E, zur Loye Hans-Conrad
Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter Street, Columbia, SC 29208, USA.
Acta Crystallogr C. 2012 Jun;68(Pt 6):i34-6. doi: 10.1107/S0108270112020513. Epub 2012 May 16.
Trilithium aluminium trimolybdate(VI), Li(3)Al(MoO(4))(3), has been grown as single crystals from α-Al(2)O(3) and MoO(3) in an Li(2)MoO(4) flux at 998 K. This compound is an example of the well known lyonsite structure type, the general formula of which can be written as A(16)B(12)O(48). Because this structure can accomodate cationic mixing as well as cationic vacancies, a wide range of chemical compositions can adopt this structure type. This has led to instances in the literature where membership in the lyonsite family has been overlooked when assigning the structure type to novel compounds. In the title compound, there are two octahedral sites with substitutional disorder between Li(+) and Al(3+), as well as a trigonal prismatic site fully occupied by Li(+). The (Li,Al)O(6) octahedra and LiO(6) trigonal prisms are linked to form hexagonal tunnels along the [100] axis. These polyhedra are connected by isolated MoO(4) tetrahedra. Infinite chains of face-sharing (Li,Al)O(6) octahedra extend through the centers of the tunnels. A mixed Li/Al site, an Li, an Mo, and two O atoms are located on mirror planes.
三钼酸锂铝（Li(3)Al(MoO(4))(3)）已通过在998 K的Li(2)MoO(4)助熔剂中，由α-Al(2)O(3)和MoO(3)生长出单晶。该化合物是著名的里昂石结构类型的一个例子，其通式可写为A(16)B(12)O(48)。由于这种结构能够容纳阳离子混合以及阳离子空位，所以多种化学成分都可以采用这种结构类型。这导致在文献中出现了一些情况，即在为新化合物指定结构类型时，忽略了其属于里昂石家族的成员身份。在标题化合物中，有两个八面体位置存在Li(+)和Al(3+)之间的替代无序，以及一个完全被Li(+)占据的三角棱柱位置。(Li,Al)O(6)八面体和LiO(6)三角棱柱相连，沿[100]轴形成六边形隧道。这些多面体通过孤立的MoO(4)四面体相连。共用面的(Li,Al)O(6)八面体的无限链贯穿隧道中心。一个Li/Al混合位置、一个Li、一个Mo和两个O原子位于镜面上。
