Investigation of Mixed Divalent Cation Monophosphates: Synthesis, Crystal Structure, and Vibrational Study of CdBa2(HPO4)2(H2PO4)2

Crystal structure and proton conductivity of a new Cs3(H2PO4)(HPO4)·2H2O phase in the caesium di- and monohydrogen orthophosphate system

“…Unlike in the known mixed divalent cation phosphates MBa 2 (HPO 4 ) 2 (H 2 PO 4 ) 2 (M = Ca, Cd, Mn) (Ben Tahar et al, 1999;Taher et al, 2001;Sun et al, 2012), only one type of phosphate tetrahedron was observed in Cs 3 (H 1.5 PO 4 ) 2 Á2H 2 O.…”

“…Three bands ($2790, 2350 and 1745 cm À1 ) are observed in the O-H stretching and bending region of the IR spectrum, confirming the presence of strong hydrogen bonds. These spectral characteristics have been observed in a variety of strong hydrogen-bonded solids having OÁ Á ÁO distances varying from 2.4 to 2.6 Å (Taher et al, 2001;Sun et al, 2012;Marchon & Novak, 1983;Baran et al, 1989). The band with a maximum lying at 2350 cm À1 and a shoulder around 2200 cm À1 may be related to the presence of two different types of hydrogen bonds with different lengths.…”

Synthesis, crystal structure, and vibrational study of K2Cu(HPO4)2·6H2O: A new metal hydrogenphosphate compound

“…As in other phosphates [28,29], the b O-H in-plane-bending vibrations occurred in the 1170À1100 cm À1 region, and the g O-H outof-plane-bending vibrations were observed in the 801e668 cm À1 interval.…”

MnBa2(HPO4)2(H2PO4)2

“…For background to transition metal phosphates, see: Cheetham et al (1999); Mao et al (2000); Mi et al (2000); Sun et al (2012);Escobal et al (1999). For isotypic structures, see : Ben Taher et al (2001) for CdBa 2 (HPO 4 ) 2 (H 2 PO 4 ) 2 ; Ben Tahar et al (1999) and Toumi et al (1997) for CaBa 2 (HPO 4 ) 2 (H 2 PO 4 ) 2 . For the bond-valence method, see: Brown (2002).…”