  Multichannel Quantum Defect Theory (MQDT) is shown to be capable of producing
quantitatively accurate results for low-energy atom-molecule scattering
calculations. With a suitable choice of reference potential and short-range
matching distance, it is possible to define a matrix that encapsulates the
short-range collision dynamics and is only weakly dependent on energy and
magnetic field. Once this has been produced, calculations at additional
energies and fields can be performed at a computational cost that is
proportional to the number of channels N and not to N^3. MQDT thus provides a
promising method for carrying out low-energy molecular scattering calculations
on systems where full exploration of the energy- and field-dependence is
currently impractical.
