X(3872): a q(q)over-bar-c(c)over-bar molecule with attractive diquarks

The q (q) over barc (c) over bar systems are investigated by a quark model with the quark correlation, which has successfully described baryon and meson mass spectra. The results show that there can be a bound state of q (q) over barc (c) over bar isospin 1, J(PC) = 1(++). This state is considered as a coupled state of the J/psi-rho and D-D* molecules. The size of the DD* component is smaller because the quark interaction is more attractive. We argue that this state can be X(3872).