The crystal structure of the phosphate eulytite Ba3Bi(PO4)3

Synthesis and Characterization of New Strontium Iron(II) Phosphates, SrFe2(PO4)2 and Sr9Fe1.5(PO4)7

“…These data will be published elsewhere. Disordering of cations in one position and PO\ tetrahedra was also observed in other phosphates, for example, with eulytite structure, Ba Bi(PO ) (37) and Sr La(PO ) (38). Some contradictions between the crystal structure re"nement and MoK ssbauer data for Sr Fe (PO ) may be explained by the following.…”

Structural Designs and Property Characterizations for Second-Harmonic Generation Materials

“…This structure composes of asymmetric Pb/BiO 6 octahedra and PO 4 tetrahedra that are interconnected via corner or edge sharing. There are three types atomic positions in the asymmetric unit of Pb 3 Bi (PO 4 ) 3 , which is different from the compound Ba 3 Bi(PO 4 ) 3 [52]. In compound Pb 3 Bi(PO 4 ) 3 , P1 and O1 atoms are occupying two single positions, atoms Pb1 and Bi1 are occupying the same position and not able to distinguish, and Pb and Bi are at fixed site occupancy ratio 3:1 equal to the ideal values in accordance with the chemical formula Pb 3 BiP 3 O 12 .…”

“…In compound Pb 3 Bi(PO 4 ) 3 , P1 and O1 atoms are occupying two single positions, atoms Pb1 and Bi1 are occupying the same position and not able to distinguish, and Pb and Bi are at fixed site occupancy ratio 3:1 equal to the ideal values in accordance with the chemical formula Pb 3 BiP 3 O 12 . It has been described in [52] that the unit cell of Ba 3 Bi(PO 4 ) 3 contains two distinguished sites for large cations (Ba1 and Bi1) and two other positions for oxygen anions (O1 and O2). The unique P 5+ cations are coordinated by four oxygen atoms to form a regular tetrahedron with the P-O distance at 1.537 Å .…”

“…It is well established that Pb 2+ and Bi 3+ ions generate distorted structures due to the electrostatic effect of the lone pair of electrons [53,54]. The structure of Pb 3 Bi(PO 4 ) 3 can also be viewed as a three-dimensional network formed by edge-sharing-mixed (Pb II /Bi III ) metal-oxygen octahedra, forming corrugated [52], there is a distinct order in the ionic radius of cations: Ba 2+ > Pb 2+ > Bi 3+ . The main structural feature of almost all eulytite-like compounds is a presence of different types of disorder in the cation or anion (or both) frameworks.…”

“…Atomic positions and the site occupancy appear to be directly related to the nature and size of the metallic cations involved in the eulytite structure. In the compound Ba 3 Bi (PO 4 ) 3 , two oxygen positions (O1 and O2) as well as peculiar sites for Ba and Bi are clearly distinguished within the lattice [52]. The Ba 2+ is bonded to twelve oxygen atoms with the Ba-O bond distances ranging from 2.662 to 2.766 Å , and the Bi 3+ is asymmetrically coordinated by six oxygen atoms to form a distorted octahedron with the Bi-O bond distances ranging from 2.378 to 2.599 Å [31].…”