Etudes structurales de composés oxyfluores du PV. II. Structure cristalline de Na2PO3Fβ

Abstract

The crystal structure of Na2PO3F fl has been studied by X-ray diffraction. This compound is orthorhombic, space group P21212x. The cell dimensions are a = 5.416 _+ 0-003, b = 6.929 +_ 0.004, c = 19.079 + 0.010 A and Z= 8. Data were measured on an automatic diffractometer using Cu K0¢ radiation, 2= 1.5418 A. The structure was established by statistical methods and refined by least-squares analysis using anisotropic thermal parameters. The structure is characterized by two kinds of POaF 2-tetrahedron. The environments of oxygen and fluorine atoms are described. The final R index is 0.052 for 712 observed reflexions.

Structural Studies of Rare Earth-Doped Fluoroborosilicate Glasses by Advanced Solid-State NMR

“…The M 2 F–Na values of F – in F–Y linkages are slightly smaller than that of F–B linkages. In the Na 2 PO 3 F crystal, per F – ion is bounded by two Na + ions within 3 Å . This indicates that per F – in these linkages is averagely bounded by approximately two Na + ions, forming Na–F–B and Na–F–Y linkages.…”

“…This is reasonable since the residual F in the glasses with the low B 2 O 3 content is more than those with the high B 2 O 3 content. Each Na + in the Na 2 PO 3 F crystal is bonded by one F – ion, according to its crystallographic structure . By comparing the M 2 Na–F values of glass samples with that of the Na 2 PO 3 F crystal, it is expected that each Na + in glasses is averagely surrounded by about 0.5–1.0 F – ions.…”

The Synthesis and Crystal Structures of Two New Hydrated Sodium Monofluorophosphates: NaHPO3F·2.5 H2O (I) and Na2PO3F·10 H2O (II)

“…On the other hand, Cs}F coordination was found in the CsHPO F structure recently reported (4). Alkali metal coordination by #uorine is also present in the Na PO F salt (12), but Ca}F bonds were not found in the hydrate of the calcium salt, CaPO F ) 2H O (13). Comparing the nonisotypic sodium compounds, Na PO F, I and II, with that of calcium (calcium and sodium have comparable ionic radii; R !…”

“…The eight water molecules, O (4) to O (11), are all hydrogen-bonded to one of the O/F atoms in the tetrahedron and another O atom. The O (12) and O (13) water molecules, which are not involved in the Na coordination, connect PO F tetrahedra to each other parallel to the c-axis (Fig. 2a).…”

Fluorine‐Driven Enhancement of Birefringence in the Fluorooxosulfate: A Deep Evaluation from a Joint Experimental and Computational Study

“…The difference in polarizability anisotropy between the fluorine‐free tetrahedral groups ((SO 4 ) 2− , (PO 4 ) 3− , [MO 4 ] (M = S, P) for short) and the fluorooxo‐tetrahedral groups ((SO 3 F) − , (PO 3 F) 2− , [MO 3 F] (M = S, P) for short) was analyzed with the combination of the first principles calculation. The optical properties of the fluorophosphates and fluorooxosulfates were calculated and analyzed in comparison with the orthophosphates and sulfates, namely, Na 3 PO 4 , [ 25 ] Na 2 PO 3 F, [ 26 ] Li 2 SO 4, [ 27 ] and LiSO 3 F, [ 28 ] and the response electronic distribution anisotropy (REDA) method was employed to discuss the bonding behavior of different groups. [ 29 ] K 2 SO 4 , [ 30 ] KSO 3 F, [ 31 ] Rb 2 SO 4 , [ 32 ] RbSO 3 F, [ 33 ] Cs 2 SO 4 , [ 34 ] CsSO 3 F, [ 33 ] (NH 4 ) 2 SO 4 , [ 35 ] and NH 4 SO 3 F [ 36 ] were calculated for optical properties as well.…”