Characterization of Zn1-xMnxSe nanowires grown by Au-catalyzed chemical vapor deposition (CVD) using transmission electron microscopy is reported. The nanostructures were found to grow in the form of nanowires, nanoribbons, and nanosaws. The fraction of manganese on the cation sublattice in the nanowires varied from x=0.1 to x=0.28. No correlation between Mn fraction and nanowire diameter was found for straight nanowires; however, in tapered nanowires the Mn fraction was found to increase as the diameter increased. The tapering, as well as the increase in Mn fraction, is likely caused by thin film deposition with a higher Mn fraction on the sides of the nanowires. Some of the nanoribbons were found to display extra diffraction spots at half-order positions in selected area diffraction. The half-order reflections were found to have originated from spontaneous atomic ordering of Mn and Zn on planes on the cation sublattice. (C) 2013 Elsevier B.V. All rights reserved.