Indium nanowires embedded in rectangular nanorods of MgO were synthesized by using the boron oxide-buffer catalytic growth method. The MgO nanorods were found to present a core of pure indium 15-20 nm in diameter. Electron diffraction analysis indicates that the embedded indium nanowires exhibit the tetragonal structure of pure indium and that the outer rectangular nanorods are face-centered cubic MgO. The orientation relationship between the indium and its MgO shell is determined to be ((1) over bar 10)(MgO)//(100)(In) and (001)(MgO)//(0 (1) over bar1)(In). (C) 2003 Elsevier B.V. All rights reserved.