1. Overview of phenomena

The importance of these surface phenomena was understood very early on. For example, J. W. Gibbs developed surface thermodynamics at the end of the 19th century. Similarly, a large body of work by I. Langmuir's work on adsorption and heterogeneous chemical kinetics has not lost its relevance, even though it dates from the early 20th century. However, with a few important exceptions, experimental studies on well-controlled surfaces were almost non-existent before the 1970s. During this decade, and especially the following one, such research was able to begin under favourable conditions thanks to the development of ultra-high vacuum, favoured by space research. Pressures of less than 10 ^-8 Pa are required to avoid surface contamination, as the reactivity of surfaces is generally very high (similar to that of free radicals). This led to the development...