Structure cristalline de 1'hydrogéno bis(dihydrogénopyrophosphate) tripotassique: K₃H(H₂P₂O₇)₂

Abstract

STRUCTURE D'HYDROGENOORTHOPHOSPHATES DE THALLIUM(I). Isant ~ une structure de sym6trie plus ~lev~e c'est-~.-dire de plus grande stabilit6 structurale qui a pour cons6-quence la creation d'une liaison H sym+trique.

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

“…The two tetrahedra share an apex (O4) to form the H 2 P 2 O 7 2À diphosphate anion in a roughly eclipsed conformation. The average P-O distance of 1.545 Å is comparable to the values of other diphosphates: 1.533 Å in (NH 4 ) 2 Zn(H 2 P 2 O 7 ) 2 Á2H 2 O, 1.537 Å in K 2 H 2 P 2 O 7 (Larbot et al, 1983) and 1.543 Å in K 3 H(H 2 P 2 O 7 ) 2 (Dumas, 1978). The P-O-P bridging angle of the bent dihydrogendiphosphate anion in (NH 4 ) 2 Co(H 2 P 2 O 7 ) 2 Á2H 2 O is 131.3 (1) .…”

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

“…The two tetrahedra share an apex (O4) to form the H 2 P 2 O 7 2À diphosphate anion in a roughly eclipsed conformation. The average P-O distance of 1.545 Å is the same as for the isotypic Co member and is comparable to the average distances observed for other diphosphates: 1.533 Å in (NH 4 ) 2 Zn(H 2 P 2 O 7 ) 2 Á2H 2 O, 1.537 Å in K 2 H 2 P 2 O 7 (Larbot et al, 1983) and 1.543 Å in K 3 H(H 2 P 2 O 7 ) 2 (Dumas, 1978).…”

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

“…The two tetrahedra share an apex (O4) to form the [H 2 P 2 O 7 ] 2À anion in a roughly eclipsed conformation. The average P-O distance of 1.533 Å can be compared to that found in K 2 H 2 P 2 O 7 (1.537 Å ; Larbot et al, 1983) and K 3 H(H 2 P 2 O 7 ) 2 (1.543 Å ; Dumas, 1978). H 2 P 2 O 7 is generally characterized by the bridging P-O-P angle, which is 128.85 (6) , a value close to that of 130.8 found in K 2 Zn(H 2 P 2 O 7 ) 2 Á2H 2 O and 130.3 in K 4 P 2 O 7 Á3H 2 O (Robertson & Calvo, 1967).…”