  We obtain a quantum dimer model (QDM) containing a Rokhsar-Kivelson (RK)
point expressed by spin-1/2 Heisenberg antiferromagnets on a diamond-like
decorated square lattice. This lattice has macroscopically degenerated
nonmagnetic ground states, which are equivalent to the Hilbert space of a
square-lattice QDM. Then, a square-lattice QDM containing the RK point as a
second-order effective Hamiltonian is obtained by introducing further neighbor
couplings as perturbation. Our model can provide a new method for the
experimental realization of a resonating valence bond state in the QDM.
