The ab initio many-electron calculation of electronic bound states coupled to the ionization continuum, i.e. the autoionization resonances, is a highly challenging task due to the ionization continuum involved. Recently, advances were reported where conventionally used ab initio codes can be employed to compute autoionization resonances. This is made possible by the use of analytical continuation tools such as complex scaling and complex absorbing potential in the electronic structure codes [1,2]. I shall present the formulation and the use of complex scaling and complex absorbing potential in many-body methods for the electron correlated calculation of energy position and autoionization decay rate. The implementation and use of analytically continued coupled-cluster method will also be discussed. With the help of these high level ab initio methods, we have recently shown that the free-electron can act as a catalyst for chemical reactions . Our work in this direction will also be presented here.