FeLi[PO4]: Dissection of a Crystal Structure - Inorganic 3D Structures - page 89

maintenance of the alloy structures in their respective oxides [ 11 , 13 , 14 ]. Thus, the
structure of FeS (NiAs) remains when the O atoms are added to form Fe[SO 4 ] and
persists, in FeLi[PO 4 ], when the Li atoms are present. Through this dissection, it is
evident that the structures are not a mere set of spheres, mainly dominated by their
size, but atoms arrange in a concerted manner so that each atom provokes (influ-
ences) the formation of the structures of the others, always leading to structures of
recognizable simpler compounds.
The phase transition triphylite

! b -FeLi[PO 4 ] can now be understood by the

need of a PbO-type NiAs transition in the [FeP] subarray. Once again, we can

state that cations govern the structures and that they undergo their own phase
transitions, even in the presence of “foreign atoms”, as previously reported [ 4 ] .
In view of this, we feel necessary to claim again for the statement of Won-
dratschek, Merker and Schubert [ 12 ] heading this article. The principle seems to
be the EZKC.

!

Acknowledgements I am indebted to my colleagues David Santamar ´ a-P ´ rez and Javier Garc ´ a
for their patient reading of the manuscript and valuable suggestions.

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¼