The liquidus-solidus phase diagram of strontium barium niobate, Sr(x)rBa(1-x)Nb(2)O(6), is determined over the whole existence region of the tetragonal phase. For this purpose, single crystals of various compositions within this range were grown. The compositions of the melts and the grown crystals as well as the corresponding liquidus temperatures were accurately determined. The tetragonal phase was found to exist from a lower limit with the crystal composition x = 0.26 to an upper limit of x = 0.87. The respective liquidus temperatures vary between 1452 and 1492degreesC. (C) 2004 Elsevier B.V. All rights reserved.