  We investigate the calculation of the magnetic form factors of nano-objects
with complex geometrical shapes and non homogeneous magnetization
distributions. We describe a numerical procedure which allows to calculate the
3D magnetic form factor of nano-objects from realistic magnetization
distributions obtained by micromagnetic calculations. This is illustrated in
the canonical cases of spheres, rods and platelets. This work is a first step
towards a 3D vectorial reconstruction of the magnetization at the nanometric
scale using neutron scattering techniques.
