Gagor Anna
W. Trzebiatowski Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna str. 2, PO Box 1410, 50-950 Wrocław, Poland.
Acta Crystallogr Sect E Struct Rep Online. 2009 Oct 28;65(Pt 11):i81. doi: 10.1107/S1600536809044043.
The crystal structure of K(5)PrLi(2)F(10) is isotypic with those of other K(5)RELi(2)F(10) compounds (RE = Eu, Nd). The lanthanoid ions are isolated in K(5)PrLi(2)F(10), with a mean separation between the Pr ions of 7.356 Å. It classifies this crystal as a so-called self-activated material containing lanthanoid ions within the matrix. Except for two K(+) and two F(-) ions, all atoms are located on sites with m symmetry. In the structure, distorted PrF(8) dodeca-hedra and two different LiF(4) tetra-hedra share F atoms, forming sheets parallel to (100). The isolated PrF(8) dodeca-hedra exhibit a mean Pr-F distance of 2.406 Å. The K(+) cations are located within and between these sheets, leading to highly irregular KF(x) polyhedra with coordination numbers of eight and nine for the alkali metal cations.
K(5)PrLi(2)F(10)的晶体结构与其他K(5)RELi(2)F(10)化合物（RE = Eu、Nd）的晶体结构同型。在K(5)PrLi(2)F(10)中镧系离子是孤立的，Pr离子之间的平均间距为7.356 Å。这将该晶体归类为一种所谓的自激活材料，其基质中含有镧系离子。除了两个K(+)和两个F(-)离子外，所有原子都位于具有m对称性的位置上。在该结构中，畸变的PrF(8)十二面体和两种不同的LiF(4)四面体共享F原子，形成平行于(100)的片层。孤立的PrF(8)十二面体的平均Pr - F距离为2.406 Å。K(+)阳离子位于这些片层内部和之间，导致形成高度不规则的KF(x)多面体，碱金属阳离子的配位数为八和九。
