On the ability of monocentric close-coupling expansions to describe ionization in atomic collisions B. Pons Centre Lasers Intenses et Applications, Universite de Bordeaux-I, 351 Cours de la Liberation, 33405 Talence, France The ability of monocentric close-coupling expansions to describe ionization is studied in the case of antiproton+H(1s) collisions. Expansions in terms of Slater Type Orbitals are first considered. Although they provide reliable ionization cross sections, the evolution of electronic distributions shows that they are unable to describe genuine ionization. A better description of the continuum, in terms of Spherical Bessel Functions, is proposed and the ability of this new new expansion to describe properly the ionization dynamics is shown.