Lattice constant variations in finely divided magnesium oxide

Abstract

The lattice parameter of MgO has been measured as a function of crystallite size at room temperature and at temperatures up to ∼1050°C. Atmosphere has a pronounced effect on lattice parameter, traces of moisture causing lattice dilation. In the absence of water vapour or adsorbed gases a lattice contraction was observed, the magnitude of which increased with decreasing crystallite size. The data obtained in this work have been compared with those predicted theoretically.