On the Crystal Structure of Nd 5 Mo 3 O 16 + δ in the Pressure Range 0–5.9 GPа

Neodymium molybdate with a cubic fluorite-like structure is obtained by solid state reactions from metal oxides. The formation of the final product occurs through the formation at 700°C of a monoclinic Ln 2 MoO 6 -type structure (space group C 2/ c ) probably containing vacancies in the neodymium and oxygen lattices. Neodymium molybdate obtained at 900°C crystallizes in the space group Pn 3̅ n with the cell parameter a ≈ 11.039 Å. The crystal structure of neodymium molybdate obtained at 700 and 900°C is studied by neutron diffraction and atomistic modeling using the GULP program in the pressure range 0–5.9 GPa, which demonstrates stability of the cubic structure at elevated pressures.