  We study the effect of nanowire shape on mechanical properties and
deformation behaviour of Cu nanowires using atomistic simulations. Simulations
were carried out on $[100]$ nanowires with different shapes such as triangular,
square, pentagon, hexagon and circular.Results indicate yield strength is
different for different shapes. In both cases, triangular nanowire exhibit the
lowest yield strength, while circular nanowire is the strongest. Deformation in
all the nanowires is dominated by partials slip and twinning. Due to twinning,
different shapes expose different surfaces at the twinned region. All nanowires
show ductile failure and square nanowire exhibits the highest failure strain,
while it is lowest for triangular nanowire.
