How to calculate metal deficiency in non stoichiometric defects eg. In fe0.93 O and Ni0.98 O . what is %age of ni+2 and ni+

Atomic imperfections / point defects:If the deviation occurs because of missing atoms, displaced atoms or extra atoms, the imperfection is named as a point defect. Such defects can be the result of imperfect packing during the original crystallisation or they may arise from thermal vibrations of atoms at elevated temperatures because with increase in thermal energy there is increased probability of individual atoms jumping out of their positions of lowest energy.Type of point defects – point defects in a crystal may be classified into three typesStoichiometric defectsNon – stoichiometry defectsImpurity defects