Three new acid M⁺ arsenates and phosphates with multiply protonated As/PO₄ 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://ucrisportal.univie.ac.at/de/publications/282bfd95-d12b-42c4-ae6d-a6dd9b0ce691