A review is given of calorimetric methods for the determination of the
heat of adsorption of gases on surfaces at least partially defined fo
r their crystal structure and cleanliness, i.e. on filaments, vacuum-e
vaporated films and single crystals of metals. The main features of th
e particular methods are mentioned, and the contribution of the obtain
ed results to the development of insight into the physics and chemistr
y of surface processes is outlined. (C) 1998 Elsevier Science B.V.