Synthesis, crystal structure and vibrational spectra of a new diammonium zinc(II) dihydrogendiphosphate dihydrate, (NH₄)₂Zn(H₂P₂O₇)₂·2H₂O

Abstract

Key indicatorsSingle-crystal X-ray study T = 301 K Mean (P-O) = 0.002 Å R factor = 0.032 wR factor = 0.090 Data-to-parameter ratio = 11.5For details of how these key indicators were automatically derived from the article, seeThe coordination around P V and Zn II in (NH 4 ) 2 Zn(H 2 P 2 O 7 ) 2 Á2H 2 O. Displacement ellipsoids are drawn at the 50% probability level.[Symmetry code: (i) Àx, 1 À y, Àz.]

Two new acidic diphosphates Rb2M(H2P2O7)2·2H2O (M = Zn and Mg): Crystal structures and vibrational study

“…The modes lying between 40 and 350 cm −1 are attributed to the external, torsional and POP deformation modes, the ı(POP) is observed between 300 and 325 cm −1 , this band was observed at 300 cm −1 in K 2 Mg(H 2 P 2 O 7 ) 2 ·2H 2 O [15] and at 317 cm −1 in Na 4 Mg 2 (H 2 P 2 O 7 ) 4 ·8H 2 O [38] and the rocking and the PO 2 deformation modes are observed in the 330-640 cm −1 region [15,16] (Fig. 4).…”

“…Moreover, some weak bands are most likely overlapped by much stronger bands and other bands are observed as weak shoulders. The interpretation of Raman and infrared spectra can be made in terms of PO 2 group, P-OH bond, POP bridge and H 2 O [14][15][16][17]. Table 4 shows band assignments for the observed modes of these dihydrogen-diphosphates.…”

“…Single crystals of Rb2M(H2P2O7)2·2H2O, M = Zn (I) and Mg (II), have been prepared according to the method elsewhere reported in some of our previous works [14][15][16][17][18][19][20][21][22]28]. In the present study, we dissolved stoichiometric amounts of Rb2CO3 (1 mmol, 0.2277 g) and MCl2·6H2O Index ranges …”

“…We undertook a serial study in our research group since a while on the system (A, M) x (H 2 P 2 O 7 ) y ·nH 2 O [A = alkaline earth or ammonium and M = a divalent 3d transition metal (including Zn) or Mg]. We did publish crystal structures from the following phosphates (NH 4 ) 2 M(H 2 P 2 O 7 ) 2 ·2H 2 O with M = Co [14], Ni [15], Zn [16]. The Mn term of this series has been reported by Capitelli et al [17].…”

(NH4)2[Ni(H2P2O7)2(H2O)2]

“…Recently, we published the structures of two acidic diphosphates (NH 4 ) 2 Zn(H 2 P 2 O 7 ) 2 Á2H 2 O (Essehli et al, 2005a) [which was published at the same time by Capitelli et al (2005)] and (NH 4 ) 2 Co(H 2 P 2 O 7 ) 2 Á2H 2 O (Essehli et al, 2005b). These two dihydrogenediphosphates are isotypic with (NH 4 ) 2 Mn(H 2 P 2 O 7 ) 2 Á2H 2 O (Capitelli et al, 2004).…”