X-ray diffraction texture analysis is employed to study heteroepitaxial layers of indium grown on GaAs(100) surfaces by molecular beam epitaxy. The results document the epitaxial relationshipsIn{101}∥GaAs{111}andIn⟨100⟩∥GaAs⟨110⟩.Furthermore, an In{101} plane is oriented nearly parallel to another GaAs{111} plane, with angular deviation less than 3.9°. Due to the symmetry of the zincblende structure, for each GaAs(111) plane, In crystallites are detected in three equivalent positions. The growth of In layers was strongly influenced by the polar character of the GaAs structure, because indium was found to grow preferably on{111}Aplanes. ©1997 American Institute of Physics.