The development of modern nanoelectronics relies crucially on the identification of various novel types of quantized structures. In particular, the artificially synthesized quantum 1D structures show a variety of intriguing physical phenomena distinct from their bulk counterparts due to the confinement of electrons in only one direction. In most of the 1D structures, the significantly enhanced couplings between charge, lattice, and spin degrees of freedom could lead to exotic phenomena such as Peierls instability, spin orderings, and the formation of Luttinger-liquid ground state. Besides the presence of exotic ground states, potentially even more intriguing are their elementary excitations. I will present a combined STM and first-principles study for the structural and electronic properties of quasi-1D indium chains on Si(111) surface, including the structure, energetics, and dynamics of topological solitary excitations or solitons at the atomic scale. I will also introduce a long-standing goal to create magnetism in a non-magnetic material by manipulating its structure at the nanoscale. Many structural defects have unpaired spins; an ordered arrangement of these can create a magnetically ordered state. I demonstrate theoretically that the dangling-bond wires fabricated on silicon surfaces and graphene achieve this state with polarized electron spins. The integration of structural and magnetic order is crucial for technologies involving spin-based computation and storage at the atomic level.