The different levels of hybridization of the
4f electron with the conduction band in
Ce compounds give rise to a wide variety of magnetic and electronic properties which allows
the analysis of different aspects of the e-e interactions. In particular,
CeM
2Si
2 compounds and their alloys (
M
being a 3d or 4d transition metal) present different physical behaviors such as long range magnetic
order, heavy fermion character, paramagnetism, non-magnetic order with magnetic correlations, and
superconductivity among others. In this work we obtain the hybridization function,
, of several
CeM
2Si
2 systems performing
ab-initio
calculations. This function gives information about the energy distribution of the hybridization
of the
4f state with the conduction band. We solve the Anderson Impurity Hamiltonian with
the
Non-Crossing Approximation taking
as an input parameter. With this many body approach
we study the crystal electric field splittings of the
4f level, the spectral properties and
some aspects of the Kondo phenomena.