  Photon-nuclear reaction in a transport model frame, namely an Extended
Quantum Molecular Dynamics (EQMD) model, has been realised at the photon energy
of 70-140 MeV in the quasi-deuteron (QD) regime. For an important application,
we pay a special focus on photonuclear reactions of
$^{12}$C($\gamma$,np)$^{10}$B where $^{12}$C is considered as different
configurations including $\alpha$-clustering. Obvious differences for some
observables have been observed among different configurations, which can be
attributed to spatial-momentum correlation of a neutron-proton pair inside
nucleus, and therefore it gives us a sensitive probe to distinguish the
different configurations including $\alpha$ clustering with the help of the
photonuclear reaction mechanism.
