Oscillations in gas-grain astrochemical kinetics

We have studied gas-grain chemical models of interstellar clouds to search for nonlinear dynamical evolution. A prescription is given producing oscillatory solutions when a bistable solution exists in the gas-phase chemistry and we demonstrate existence limit cycle relaxation oscillation solutions. As autocatalytic processes underlying these are common all chemistry, occurrence should be widespread. briefly discuss implications interpreting molecular cloud composition with time-dependent some future directions this approach.