  A generalized class of ultra-long-range Rydberg molecules is proposed which
consist of a multichannel Rydberg atom whose outermost electron creates a
chemical bond with a distant ground state atom. Such multichannel Rydberg
molecules exhibit favorable properties for laser excitation, because states
exist where the quantum defect varies strongly with the principal quantum
number. The resulting occurrence of near degeneracies with states of high
orbital angular momentum promotes the admixture of low $l$ into the high $l$
deeply bound `trilobite' molecule states, thereby circumventing the usual
difficulty posed by electric dipole selection rules. Such states also can
exhibit multi-scale binding possibilities that could present novel options for
quantum manipulation.
