Hydrothermal Synthesis and Magnetic Behaviour of β-Li3VF6 and Na3VF6.

Single crystals of β-Li3VF6 (I) and Na3VF6 (II) are obtained by hydrothermal reaction of stoichiometric amounts of NH4VO3, NH4HF2, LiCl (NaCl), and fumaric acid (pH 4—6, autoclave, 240 °C, 24 h) without the need for HF.