Synthesis and crystal structure of a gallium phosphate with 14-ring channels

The synthesis and crystal structure of a new 14-membered ring gallium oxyfluorophosphate are described: DIPYR-GaPO: Ga7P6O28F3C10N2H16 , Mr=1343.1, space group P , a=12.000(3) Å, b=13.895(4) Å, c=10.280(4) Å, alpha;=101.09(3)°, beta;=100.91(2)°, gamma;=106.41(2)°, Dc=2.83 g cm–3 , F(000)=1297, R=2.89%, Rw=3.63%. The product was obtained by hydrothermal synthesis at 170 °C in a reaction using two amines as structure-directing agents in the HF–Ga2O3–P2O5 system: pyridine and benzylviologen dichloride. The benzylviologen dichloride decomposed during the reaction to form 4,4′-dipyridyl, which was found in the 14-ring channels together with pyridine. Intraframework hydrogen bonding appears to play an important role in determining the shape of the pores.