Atomistic study on twinning of Cu2O quantum dots

Cu2O nanoparticles are investigated at atomic scale by high-resolution transmission electron microscopy. It is found that growth {111} twinning is the most common type of defects in these nanoparticles. The atomic structure of the twinning boundaries is determined referring to the detailed image simulations based on the structure model refined by first-principles calculation. The twin boundary plane is along a {111} oxygen plane and the twinning shows a crystallographic relation with a symmetry operation of 180 degrees rotation around a < 111 > axis perpendicular to the plane. The effect of the twinning on the stability of the particles is discussed. (c) 2006 American Institute of Physics.