Spin-orbit force, recoil corrections, and possible B(B)over-bar* and D(D)over-bar* molecular states

In the framework of the one-boson exchange model, we have calculated the effective potentials between two heavy mesons B (B) over bar* and D (D) over bar* from the t- and u-channel pi-, eta, rho-, omega-, and sigma-meson exchanges with four kinds of quantum number: I = 0, J(PC) = 1(++); 1 = 0, J(PC) = 1(+-); I = 1, J(PC) = 1(++); I = 1, J(PC) = 1(+-). We keep the recoil corrections to the B (B) over bar* and D (D) over bar* systems up to O(1/m(2)) The spin-orbit force appears at O(1/M), which turns out to be important for the very loosely bound molecular states. Our numerical results show that the momentum-related corrections are unfavorable to the formation of the molecular states in the I = 0, J(PC) = 1(++) and I = 1, J(PC) = 1(+-) channels in the D (D) over bar* system.