CuSeO4 and Cu(SeO3OH)(2)6H(2)O, two novel copper-selenium(VI) oxysalts
- Author(s)
- Herta S. Effenberger, Gerald Giester, Manfred Wildner
- Abstract
The two new copper(II) salts Cu(SeO
4) and Cu(SeO
3OH)
2·6H
2O were synthesized at low-temperature hydrothermal conditions (220 °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) Å, β = 94.82(1)°, Z = 4; P1 ¯ , a = 6.133(1), b = 6.303(1), c = 8.648(2) Å, α = 70.45(1), β = 84.60(1), γ = 73.44(1)°, Z = 1]. Cu(SeO
4) adopts the MnAsO
4 structure type. It exhibits structural as well as topological relations with two formerly known isochemical compounds. They crystallize in the structure type ZnSO
4 (mineral name zincosite, Pnma) respectively NiSO
4 (Cmcm). The two minerals dravertite, CuMg(SO
4)
2, and hermannjahnite, CuZn(SO
4)
2, are isotypic with CuSeO
4-P2
1/n; interestingly, also α-NaCu(PO
4) belongs to this structure type: some rotation of the XO
4 group allows a supplementary position for the Na atom. — Cu(SeO
3OH)
2·6H
2O represents a new structure type. The protonated selenate group shows an extended Se—O
h bond distance (1.695 Å) as compared to the other Se—O bonds (1.614 to 1.626 Å). One OH dipole of the three independent H
2O molecules represents a rather free hydrogen bond. For the other H atoms, the O—H···O lengths vary from 2.585 to 2.799 Å. Interestingly, the distance O
w7···O
w7 of only 2.791 Å does not represent an edge in a coordination polyhedron and it is not preliminary involved in the hydrogen bond scheme. All Cu
2+ ions in the two title compounds are in a pronounced [4 + 2] coordination. The Cu
2+[4+2] atoms in Cu(SeO
4) are linked to chains along [100]; in Cu(SeO
3OH)
2·6H
2O they are not connected among each other.
- Organisation(s)
- Department of Mineralogy and Crystallography
- Journal
- Mineralogy and Petrology
- Volume
- 117
- Pages
- 307-315
- No. of pages
- 9
- ISSN
- 0930-0708
- DOI
- https://doi.org/10.1007/s00710-022-00809-8
- Publication date
- 2023
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105116 Mineralogy, 105105 Geochemistry
- Keywords
- ASJC Scopus subject areas
- Geochemistry and Petrology, Geophysics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/8b165ebd-882f-4e8d-af48-13db586925d9