A V(IV) Tetraphosphate with a Tunnel Structure K2(VO)2P4O13

✍ Scribed by M.M. Borel; A. Leclaire; J. Chardon; J. Provost; H. Rebbah; B. Raveau

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 668 KB
• Volume: 132
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1997.7404

✦ Synopsis

A V(IV) tetraphosphate K 2 (VO) 2 P 4 O 13 has been synthesized for the first time, and crystals of this new phase can be grown in air. It crystallizes in the space group Pbca with a ‫؍‬ 22.181(2)A s , b ‫؍‬ 11.564(1)A s , c ‫؍‬ 9.948(1)A s . The original structure of this phase consists of corner sharing P 4 O 13 tetraphosphate groups and VO 6 octahedra forming a tridimensional framework [V 2 P 4 O 15 ]

. The latter delimits large tunnels running along c and small tunnels running along b and [1 0 1], where two kinds of sites K(1) and K(2) are occupied by potassium. The horseshoe conformation of the P 4 O 13 group is different from those observed previously which are principally S shaped. The magnetic susceptibility investigation shows a paramagnetic behavior, with a C parameter of 1.55 B . The thermogravimetric study shows the exceptional stability of V(IV) in this phosphate matrix, whatever the atmosphere air or oxygen up to 750°C.