Neutron powder diffraction study and DFT calculations on the structure of Zr10Sc4O26
Zeitschrift Fur Kristallographie 224(11): 539-543
Powder neutron diffraction was used to investigate Zr10Sc4O26, the so called gamma-phase in the zirconia scandia system. This fluorite related anion deficient compound with composition MX1.86 crystallizes in space group R (3) over bar and lattice constants a = 952.7(3) pun and c = 1745.3(4) pm. Anion vacancies are inserted on the 6c sites in R (3) over bar. The neutron data as well as the periodic density-functional calculations performed count for a divacancy model. The paired defect is more stable by 29 kJ/mol than any model with Unpaired vacancies including the model with the 1/2 (F) (index F = fluorite) vacancy separation along an empty anion Cube.