Synthesis, crystal structure and vibrational spectra characterization of MILa(PO3)4 (MI=Na, Ag)

Abstract

The single crystals of lanthanum metaphosphate MLa(PO 3) 4 (M=Na, Ag) have been synthesized and studied by a combination of X-ray crystal diffraction and vibrational spectroscopy. The sodium and silver compounds crystallize in the same monoclinic P2 1 /n space group (factor group) with the following respective unit cell dimensions: a=7.255(2), b=13.186(3), , β=90.40(2)°, , Z=4 and a=7.300(5), b=13.211(9), , β=90.47(4)°, , Z=4. This threedimensional framework is built of twisted zigzag chains running along a direction and made up of PO 4 tetrahedra sharing two corners, connected to the LaO 8 and NaO 7 or AgO 7 polyhedra by common oxygen atoms to the chains. The infrared and Raman vibrational spectra have been investigated. A group factor analysis leads to the determination of internal modes of (PO 3) − anion in the phosphate chain.

Eu3+ ions co-doped CLPO: Dy3+ single phase white-light emitting phosphors for near UV-based white LEDs

“…correspond to anti-symmetric and symmetric bending modes (δ) of P-O-P and O-P-O, which are very difficult to distinguish[14]. All these bands are comparable with the reported ones[15][16][17].…”

Silver-gadolinium polytetraphosphate AgGd(PO3)4 synthesis, structural study, IR spectroscopy and conductivity investigation

“…Indeed, the fourcoordinated Ag site shows a weak underbonding ( s = 0.68) which will be significant even when the coordination number is increased to six ( s = 0.73) ( Table 2). The Ag environment is slightly different to the Ag site coordination in AgLa(PO 3 ) 4 [18]. In this latter structure, five oxygen atoms constitute the first coordination sphere around the Ag with Ag-O distance varying from 2.483(9) to 2.670(9)Å.…”

“…2 and 3, respectively. As a result of our investigations, AgGd(PO 3 ) 4 was shown to be isostructural with NaLa(PO 3 ) 4 , AgLa(PO 3 ) 4 [18] and AgNd(PO 3 ) 4 [15]. From a general point of view, this phosphate could be described as a long chain polyphosphate containing alternating (PO 3 ) n chains and (M 3+ , M + ) cations along the [0 0 1] direction.…”

Crystal growth, characterization and spectroscopic study of europium-doped NaY(PO3)4

“…The large majority of M I -(Y-Bi-Ln) polyphosphates family, where Ln was a lanthanide, corresponds to the general formula M I M III (PO 3 ) 4 . Many doublecondensed phosphates of rare earth and sodium, NaLn(PO 3 ) 4 (Ln ¼ La, Pr, Nd, Ce, Gd) are reported in the literature [14][15][16][17][18][19].…”