Ammonolysis of R2Mo2O7 pyrochlores gives R2Mo2O5N2 containing S = ½ Mo5+. They are excellent candidate materials for investigation of quantum spin liquid phenomena and we have prepared polycrystalline samples of the new pyrochlore Lu2Mo2O5N2. HRPD is requested for one day to study a sample of Lu2Mo2O5N2 at temperatures from 2 to 300 K. These data will be used to refine O/N occupancies over the two anion sites within the pyrochlore structure (making use of the excellent neutron scattering length contrast of oxygen (5.80 fm) and nitrogen (9.36 fm)), to check whether any spin order is present at 2 K, and to follow the thermal evolution of the structure and thereby determine whether any phase transitions occur on cooling. These results are needed to confirm the suitability of Lu2Mo2O5N5 for more detailed future studies of the low temperature magnetic ground state in S = ½ pyrochlores.