Divacancies and the hydrogenation of Mg-Ti films with short range chemical order

We obtained evidence for the partial chemical segregation of as-deposited and hydrogenated Mg1?yTiy films (0 ? y ? 0.30) into nanoscale Ti and Mg domains using positron Doppler-broadening. We exclusively monitor the hydrogenation of Mg domains, owing to the large difference in positron affinity for Mg and Ti. The electron momentum distribution...