Electrolyses of alkali titanate and titanate-vanadate melts at temperatures up to 1050°C have produced single crystals of a number of phases of general composition AxBO 2 where A is an alkali-metal ion and B represents a mixture of Ti 3+ and Ti 4+ or of V 3+ and Ti 4+. These phases included hexagonal Na 1.3V 1.3Ti 0.7O 4, with lattice parameters a = 2.92, c = 11.20 Å, the hollandite-types K xTi 4O 8 ( a = 10.20, c = 2.99 Å) and Cs xTi 4O 8 ( a = 10.32, c = 2.92 Å), a potassium layer compound K 0.8V 0.8Ti 1.2O 4 ( a = 3.73, b = 15.90, c = 2.98 Å) and a cesium layer compound Cs xTi 2O 4 isomorphous with Rb xMn xTi 2- xO 4, with a = 3.84, b = 18.02, c = 3.01 Å. We have also found a monoclinic sodium titanium oxide of composition near to NaTiO 2, with a = 23.4, b = 3.08, c = 11.06 Å, β = 75.25°, and an octatitanate K 3Ti 8O 17, with a = 15.68, b = 3.809, c = 12.06 Å and β = 95.0°. Electrolyses of cesium vanadate and molybdate melts have also produced new phases, including a tetragonal cesium vanadium bronze Cs 0.93V 2O 5+ x, x ≈ 0.3, with a = 7.72, c = 11.73 Å, and a monoclinic cesium molybdenum bronze Cs 0.3MoO 3. The structures of a number of the phases produced have been determined or identified. Most are poor conductors of electricity, but Cs xTi 4O 8 shows highly anisotropic semiconductivity.