Chlorovanadates with Original Chain and Layered Structures: AVO3Cl (A=Ba, Sr, Cd)
✍ Scribed by M.M. Borel; J. Chardon; A. Leclaire; B. Raveau
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 349 KB
- Volume
- 145
- Category
- Article
- ISSN
- 0022-4596
No coin nor oath required. For personal study only.
✦ Synopsis
A ؍ Cd. The structure of BaVO 3 Cl and SrVO 3 Cl consists of [BaCl] n؉ n or [SrCl] n؉ n chains running along b forming a distorted 99honeycomb:: lattice whose tubes are occupied by [VO 3 ] n؊ n chains built up of edge-sharing square pyramids. The CdVO 3 Cl structure can be described as the assemblage of rutile type layers [Cd 6 Cl 6 O 7 ]
interconnected by [V 6 O 11 ] double chains of edge and corner sharing VO 5 bipyramids. The latter forms 5ve sided tunnels which are empty.
1999 Academic Press
Vanadium oxides represent a large family of compounds which have been investigated because of their wide applications, especially in the "eld of catalysis. For these reasons numerous papers about synthesis and crystal chemistry of vanadates (1), vanadium bronzes (2), and vanadium phosphates (3) have been published in the past.
In contrast, very few chlorovanadates have been synthesized to date. Considering the alkaline earth chlorovanadates, only two series of compounds are actually known. The "rst series, with the formula A (VO ) Cl, obtained for A"Ca, Sr, Ba (4), exhibits the apatite structure, whereas the second one corresponds to the formula A VO Cl with A"Ca, Sr (5, 6) and exhibits the spodiosite structure.
In the present study we have investigated the systems AO}V O }ACl for A"Sr, Ba, Cd. We report herein on new chlorovanadates AVO Cl which exhibit original structures. Two of them, BaVO Cl and SrVO Cl, exhibit a chain structure, whereas the third one, CdVO Cl, has a layered structure built up from distorted rutile slabs interconnected through double pyramidal vanadium chains.