  A mode-coupling theory for the slow single-particle dynamics in fluids
adsorbed in disordered porous media is derived, which complements previous work
on the collective dynamics [V. Krakoviack, Phys. Rev. E 75, 031503 (2007)]. Its
equations, like the previous ones, reflect the interplay between
confinement-induced relaxation phenomena and glassy dynamics through the
presence of two contributions in the slow part of the memory kernel, which are
linear and quadratic in the density correlation functions, respectively. From
numerical solutions for two simple models with pure hard core interactions, it
is shown that two different scenarios result for the diffusion-localization
transition, depending on the strength of the confinement. For weak confinement,
this transition is discontinuous and coincides with the ideal glass transition,
like in one-component bulk systems, while, for strong confinement, it is
continuous and occurs before the collective dynamics gets nonergodic. In the
latter case, the glass transition manifests itself as a secondary transition,
which can be either continuous or discontinuous, in the already arrested
single-particle dynamics. The main features of the anomalous dynamics found in
the vicinity of all these transitions are reviewed and illustrated with
detailed computations.
