CuSeO4 and Cu(SeO3OH)(2)6H(2)O, two novel copper-selenium(VI) oxysalts

Autor(en)
Herta S. Effenberger, Gerald Giester, Manfred Wildner
Abstrakt

The two new copper(II) salts Cu(SeO4) and Cu(SeO3OH)2middot6H2O were synthesized at low-temperature hydrothermal conditions (220 degrees C), and room temperature, respectively. Their atomic arrangements were studied based on single-crystal X-ray investigations [P2(1)/n, a = 4.823(1), b = 8.957(2), c = 6.953(1) A, beta = 94.82(1)degrees, Z = 4; P(1) over bar, a = 6.133(1), b = 6.303(1), c = 8.648(2) A, alpha = 70.45(1), beta = 84.60(1), gamma = 73.44(1)degrees, Z = 1]. Cu(SeO4) adopts the MnAsO4 structure type. It exhibits structural as well as topological relations with two formerly known isochemical compounds. They crystallize in the structure type ZnSO4 (mineral name zincosite, Pnma) respectively NiSO4 (Cmcm). The two minerals dravertite, CuMg(SO4)(2), and hermannjahnite, CuZn(SO4)(2), are isotypic with CuSeO4-P2(1)/n; interestingly, also alpha-NaCu(PO4) belongs to this structure type: some rotation of the XO4 group allows a supplementary position for the Na atom. - Cu(SeO3OH)2middot6H(2)O represents a new structure type. The protonated selenate group shows an extended Se-Oh bond distance (1.695 A) as compared to the other Se-O bonds (1.614 to 1.626 A). One OH dipole of the three independent H2O molecules represents a rather free hydrogen bond. For the other H atoms, the O-(w)7 of only 2.791 A does not represent an edge in a coordination polyhedron and it is not preliminary involved in the hydrogen bond scheme. All Cu2+ ions in the two title compounds are in a pronounced [4 + 2] coordination. The Cu2+[4+2] atoms in Cu(SeO4) are linked to chains along [100]; in Cu(SeO3OH)(2)middot6H(2)O they are not connected among each other.

Organisation(en)
Institut für Mineralogie und Kristallographie
Journal
Mineralogy and Petrology
Band
117
Seiten
307-315
Anzahl der Seiten
9
ISSN
0930-0708
DOI
https://doi.org/10.1007/s00710-022-00809-8
Publikationsdatum
2023
Peer-reviewed
Ja
ÖFOS 2012
105116 Mineralogie, 105105 Geochemie
Schlagwörter
ASJC Scopus Sachgebiete
Geochemistry and Petrology, Geophysics
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/8b165ebd-882f-4e8d-af48-13db586925d9