Electric field gradient calculations in ZnO samples implanted with 111In(111Cd)

A first-principles study of the electric field gradient (EFG) calculated for ideal and 111In(111Cd) implanted ZnO samples is reported in the present work. The study was made for ZnO ideal hexagonal structures and supercells were introduced in order to consider the possible implantation environments. The calculation was done using the “WIEN2k” code within the density functional theory, the exchange and correlation effects were determined by the GGA approximation. Three possible 111In(111Cd) implantation configurations were studied, one substitutional incorporation at cation site and two interstitials. The obtained EFG values for the ideal structure and the substitutional site are in good agreement with the experimental reports measured by perturbed angular correlation (PAC) and high precision nuclear magnetic resonance (NMR). Thus, the ascription of substitutional incorporation of 111In(111Cd) probe atom at the ZnO cation site after annealing was confirmed.