The double perovskite compounds Sr2AlTaO6, Sr2Al0.5Ga0.5TaO6, Sr2GaTaO6, Sr2CrNbO6, and Sr2NiWO6 (a(p) = 3.900, 3.924, 3.944, 3.940, 3.941 angstrom respectively) have been investigated for use as buffer layer materials to aid in high quality thin film growth of the desired half -metallic double perovskite Sr2FeMoO6 (a(p) = 3.947 angstrom). Chosen for their closely matching lattice parameters and insulating properties, the proposed buffer materials have been deposited by pulsed laser deposition and are found to be pure phase and epitaxial. X-ray diffraction, atomic force microscopy, Rutherford backscattering, and transmission electron microscopy have been used to characterize the films' structure, surface roughness, and stoichiometry. Off-stoichiometry and structural defects are shown to allow strain relaxation of the films, thereby maintaining the smooth surfaces required for multilayer deposition. (C) 2016 Elsevier B.V. All rights reserved.