The angular momentum projected generator coordinate method using the quadru
pole moment as a collective coordinate and the Gogny force as the effective
interaction is used to describe the properties of the ground and low-lying
excited states of the neutron rich light nuclei Si-32,Si-34,Si-36. It is f
ound that the ground state of the nucleus Si-34 is spherical. However, this
is not due only to the N = 20 shell closure, since the ground state of Si-
34 contains a significant amount of the intruder f(7/2) neutron orbital. A
rather good agreement with experimental data for many observables is obtain
ed.