Synthesis and characterizations of cyclic octanuclear mixed-valence vanadium(IV,V) clusters with polyoxometalate counterions.
{Hydrothermal reaction of Na2WO4, VOSO4, 2,2'-bpy and H3PO4 has afforded in high yield [VIV2VV6O14(bpy)8(PO4)2][PW11VVO40](bpy)·12H2O (1). Compd. 1 contains a novel octanuclear mixed valence V(iv,v) cluster, [VIV2VV6O14(bpy)8(PO4)2]4+, with [PW11VVO40]4- as counterion. In the V cluster, four V(V) centers are localized and the remaining two V(IV) and two V(V) ions are disordered over four crystallog. equiv. positions. Isostructural [VIV2VV6O14(bpy)8(PO4)2][PMo11VVO40](bpy)·3H2O (2) also was synthesized. Thermodiffractometry expts. indicate that 2 is stable up to 360°. Redox activities for both the V and Mo centers were obsd. by solid-state electrochem. measurements performed on mech. attached microparticles of 2. Magnetic measurements performed on 1 showed the occurrence of weak ferromagnetic interactions between the V(IV) centers (J = +0.34 cm-1
Références
- Titre
- Synthesis and characterizations of cyclic octanuclear mixed-valence vanadium(IV,V) clusters with polyoxometalate counterions.
- Type de publication
- Article de revue
- Année de publication
- 2006
- Auteurs
- Lisnard, Laurent, Dolbecq Anne, Mialane Pierre, Marrot Jérôme, Rivière Eric, Borshch Serguei A., Petit Sébastien, Robert Vincent, Duboc Carole, McCormac Timothy, and Secheresse Francis.
- Revue
- Dalt. Trans.
- Pagination
- 5141–5148
- ISSN
- 1477-9226
- Mots-clés
- crystal structure vanadium oxo bipyridine octanuclear complex polyoxometalate salt vanadium oxo bipyridine octanuclear complex polyoxometalate anion salt prepn
- DOI
- 10.1039/B610735D
Soumis le 12 avril 2018