We present a theoretical study of the magnetic properties at finite tempera
ture of the ideal (001), (110), and (111) Fe surfaces as well as a stepped
surface. The spin-polarized electronic structure at a given temperature is
determined by solving self-consistently a one-particle d-band model Hamilto
nian in the real space, in which correlation effects are included in a temp
erature-dependent splitting parameter. We first compare our results for the
(001) crystallographic orientation with the experimental trends and with a
previous work of Hasegawa using a functional-integral method, which will s
erve us as a test. The decrease of the magnetic moment as increasing temper
ature is analyzed at the three different orientations and is compared with
the bulk case. Finally, a prototypical nonideal and more realistic system (
stepped surface) is also investigated. The applicability of the model to th
e study of other complex systems like supported clusters or surfaces with d
efects is discussed.