Atomic structures and stability of hexagonal BN, diamond and Au multiply-twinned nanoparticles with five-fold symmetry

摘要

The atomic structures and stability of hexagonal-BN, diamond and Au nanoparticles with a five-fold symmetry were investigated by high-resolution electron microscopy, electron diffraction and molecular orbital calculations. Diamond, Au and BN have {111}, {111} and {112} twin planes, and <110>, <110> and <201> five-fold axes, respectively. The sizes for diamond, BN and Au were 5 #mu#m, and 300 and 10 nm, respectively, and many stacking faults and dislocations were observed between the twin boundaries in diamond particles. BN has quite a smaller distortion compared to diamond and Au, which was also shown by molecular orbital and molecular mechanics calculations.