We show that a cylindrical quantum wire whose lateral surface is deformed m
ay support surface states localized on the deformation. This surface locali
zation can be studied upon writing the single-particle Schrodinger equation
in a curvilinear coordinates system on the surface. The energies of these
localized states depend on the parameters that characterize the surface and
numerical results for a deformed quantum wire show that the more the defor
mation is pronounced, the more the wave functions are localized on it. The
relative alignment of both volume confined and surface states is discussed
with a view to porous silicon. Insights are given on the relation between t
he formation of localized surface states and the nanostructure surface reac
tivity to a gas environment in the framework of nanostructured materials se
nsor applications.