In this talk, we review the method we proposed to use the Friedrichs-like model combined with QPC model to include the hadron interaction corrections to the spectrum predicted by the quark model, in particular the Godfrey-Isgur model. This method is then used on the first excited P-wave charmonium states, and X(3862), X(3872), and X(3930) state could be simultaneously produced with a quite good accuracy. The X(3872) state is shown to be a bound state with a large DD* continuum component. At the same time, the hc(2P) state is perdicted at about 3902 MeV with a pole width of about 54 MeV.
Inclusive decays of ηb into S- and P-wave charmonium states