In this article, we report on the fabrication of a periodic network of nanostructures through a substrate-mediated assembly of functional nanoparticles. In one experiment, periodic arrangement of steps and terraces was generated on a sapphire substrate through a unique recipe of annealing cycles. Deposition of submonolayer quantities of silicon on this surface leads to the formation of atomic lines due to the selective incorporation of silicon atoms at step edges. We also show the formation of nanomagnetic chains formed by assembling nanoparticles of Fe2O3 on graphite, silicon and germanium substrates. On-site generation of nanomagnetic particles of Fe through surface mediation is demonstrated on silicon and germanium surfaces. In these two cases, surface mediation involves reduction of Fe2O3 to Fe and their assembly along preferred sites. (C) 2008 Elsevier B. V. All rights reserved.