  We investigate properties of ultralong-range polyatomic molecules formed with
a Rb Rydberg atom and several ground-state atoms whose distance from the
Rydberg atom is of the order of n^2a_0, where n is the principle quantum number
of the Rydberg electron. In particular, we put emphasis on the splitting of the
energy levels, and elucidate the nature of the splitting via the construction
of symmetry-adapted orbitals.
