  We observe "trilobite-like" states of ultracold 85Rb2 molecules, in which a
ground-state atom is bound by the electronic wavefunction of its Rydberg-atom
partner. We populate these states through the ultraviolet excitation of
weakly-bound molecules, and access a regime of trilobite-like states at low
principal quantum numbers and with vibrational turning points around 35 Bohr
radii. This demonstrates that, unlike previous studies that used free-to-bound
transitions, trilobite-like states can also be excited through bound-to-bound
transitions. This approach provides high excitation probabilities without
requiring high-density samples, and affords the ability to control the
excitation radius by selection of the initial-state vibrational level.
