Three new acid M<sup>+</sup> arsenates and phosphates with multiply protonated As/PO<sub>4</sub> groups

Autor(en)
Karolina Schwendtner, Uwe Kolitsch
Abstrakt

The crystal structures of caesium dihydrogen arsenate(V) bis[trihydrogen arsenate(V)], Cs(H2AsO4)(H3AsO4)2, ammonium dihydrogen arsenate(V) trihydrogen arsenate(V), NH4(H2AsO4)(H3AsO4), and dilithium bis(dihydrogen phosphate), Li2(H2PO4)2, were solved from single-crystal X-ray diffraction data. NH4(H2AsO4)(H3AsO4), which was hydrothermally synthesized (T = 493 K), is homeotypic with Rb(H2AsO4)(H3AsO4), while Cs- (H2AsO4)(H3AsO4)2 crystallizes in a novel structure type and Li2(H2PO4)2 represents a new polymorph of this composition. The Cs and Li compounds grew at room temperature from highly acidic aqueous solutions. Li2(H2PO4)2 forms a three-dimensional (3D) framework of PO4 tetrahedra sharing corners with Li2O6 dimers built of edge-sharing LiO4 groups, which is reinforced by hydrogen bonds. The two arsenate compounds are characterized by a 3D network of AsO4 groups that are connected solely via multiple strong hydrogen bonds. A statistical evaluation of the As-O bond lengths in singly, doubly and triply protonated AsO4 groups gave average values of 1.70 (2) A ° for 199 As-OH bonds, 1.728 (19) A ° for As-OH bonds in HAsO4 groups, 1.714 (12) A ° for As-OH bonds in H2AsO4 groups and 1.694 (16) A ° for As-OH bonds in H3AsO4 groups, and a grand mean value of 1.667 (18) A ° for As-O bonds to nonprotonated O atoms.

Organisation(en)
Institut für Mineralogie und Kristallographie
Externe Organisation(en)
Technische Universität Wien, Naturhistorisches Museum Wien (NHM)
Journal
Acta Crystallographica. Section C: Structural Chemistry
Band
C75
Seiten
1134-1141
Anzahl der Seiten
8
ISSN
2053-2296
DOI
https://doi.org/10.1107/S2053229619008489
Publikationsdatum
08-2019
Peer-reviewed
Ja
ÖFOS 2012
104011 Materialchemie, 105113 Kristallographie
Schlagwörter
ASJC Scopus Sachgebiete
Condensed Matter Physics, Materials Chemistry, Inorganic Chemistry, Physical and Theoretical Chemistry
Link zum Portal
https://ucris.univie.ac.at/portal/de/publications/three-new-acid-m-arsenates-and-phosphates-with-multiply-protonated-aspo4-groups(282bfd95-d12b-42c4-ae6d-a6dd9b0ce691).html