Spin structure functions of the proton and the neutron at low to moderate Q$^2$

The physics program with CLAS at the Jefferson Lab has collected a large amount of data on the spin structure functions of the nucleon by using polarized electron beam directed on polarized NH$_3$ and ND$_3$ targets. In these experiments, the virtual photon asymmetry $A_1$ and the spin structure function $g_1$ were measured with an unprecedented precision in a large kinematic range of 0.01 GeV$^2$ $<$ Q$^2$ $<$ 6.0 GeV$^2$ and 1.08 GeV $< W <$ 3.0 GeV. The data help us to better understand the spin structure of the nucleon, especially in the transition region between hadronic and quark-gluon degrees of freedom. Therefore, it will be possible to put limits on quark-hadron duality, test pQCD predictions for the quark polarization at large $x$, perform more precise calculations of higher-twist matrix elements in the framework of the Operator Product Expansion and get a glimpse of A$_1$ at high $x$. In addition, using available proton and deuteron data together and utilizing a new unfolding technique, the spin structure functions for the neutron in the resonance region are extracted.