Preparation, Crystal Structure, Vibrational Spectra, and Thermal Behavior of Rb₂H₂P₂O₆·2H₂O

Abstract

Single crystals of Rb2H2P2O6·2H2O could be obtained from aqueous solutions of hypodiphosphoric acid and rubidium carbonate. Its crystal structure was determined by X‐ray diffraction and it crystallizes in the monoclinic space group P21/c with Z = 4. The salt‐like title compound consists of [H2P2O6]2– units in staggered P2O6‐skeleton conformation, Rb+ cations, and H2O molecules, held together by intermolecular hydrogen bonds of the type O···O. The vibrational spectra (IR/FIR and Raman) of the rubidium salt were recorded and an assignment of the vibrational modes is proposed based on the point group C2h for the P2O6‐skeleton of the anion. The thermal behavior of Rb2H2P2O6·2H2O is dominated by a complex TG decay indicating a simultaneous H2O delivery coupled with a disproportionation of [H2P2O6]2–, what is also supported by Raman spectra of heated samples.

Adenosine hypodiphosphate ester, an analogue of ADP: analysis of the adenine–hypodiphosphate interaction mode in hypodiphosphate nucleotides and adenine salts

“…From the crystal structures of inorganic salts it is known that the typical conformation of hypodiphosphate is a staggered arrangement with the O-P-P-O torsion angles close to 60 and 180 . The only exception reported up to now is a series of isomorphous K 2 [M(H 2 P 2 O 6 ) 2 -(H 2 O) 2 ]ÁH 2 O double salts (M = Co, Ni, Cu and Zn; Gjikaj & Wu, 2014), where the H 2 P 2 O 6 2À anions adopt an eclipsed conformation, with the smallest O-P-P-O torsion angle of 0.04 (12) . In the nucleoside esters presented here, the hypodiphosphate groups exist in an intermediate (between eclipsed and staggered) arrangement, with the smallest O-P-P-O torsion angle being 23.6 (18) in AhDP-B in (II).…”

Three Crystal Structures, One Chemical Formula – Barium Dihydrogen‐hypodiphosphate(IV)‐dihydrate, BaH2P2O6·2H2O

“…Die anderen H‐Brücken bestehen zwischen H 2 O‐Molekülen und [H 2 P 2 O 6 ] 2– ‐Ionen (mit O–H ··· O‐Abständen von 2,830 bis 3,017 Å und O–H ··· O‐Winkeln von 139,8 bis 174,0 °). Analog zu Rb 2 H 2 P 2 O 6 · 2H 2 O weist auch diese Verbindung zwischen den [H 2 P 2 O 6 ] 2– ‐Anionen kürzere H‐Brücken auf als zwischen Anionen und Wassermolekülen (Tabelle ).…”

Preparation, Crystal Structure, Vibrational Spectra, and Thermal Behavior of Tl2H2P2O6 and Tl4P2O6

“…[12] The structure exhibits a three-dimensional hydrogen-bonded network (Figure 3) The X-ray diffraction pattern of the title compound, Tl 2 H 2 P 2 O 6 (1), were measured at room temperature with a STOE STADI P diffractometer with a Debye-Scherrer setup. Phase analysis was carried out by using the JANA2006 [16] program.…”

“…[3] On the basis of the acidity of the hypodiphosphoric acid [4] the crystal structures of Na 2 [5][6][7][8][9] as well as those of potassium salts [10,11] and very recently the structure of rubidium salt. [12] Herein, we report the synthesis, the single-crystal structures, the IR/Raman spectra, and thermogravimetric (TG) measurements of thallium hypodiphosphates(IV) Tl 2 H 2 P 2 O 6 (1) and Tl 4 P 2 O 6 (2). 2-groups consolidate the structure 1 into a three-dimensional network.…”