Anionic multipole polarisabilities of alkali earth oxides and sulfides nanocrystals

We generalize two parameters trial wave function in the Kirkwood-Pople and Schofield approach to obtain multipole moments for atoms or ions. Madelung factor is calculated for bulk rocksalt structure nanocrystal. Then we apply our generalized approach to calculate ionic electronic polarisabilities such as dipole, quadrupole and octupole polarisabilities of O−2 and S−2 ions at different sphere potentials and in MgO, CaO, SrO, BaO and MgS, CaS, SrS, BaS bulk crystal. This generalized approach with Madelung factor is also applied for bulk nanocrystals. Results reveal that the ionic electronic polarisabilites are very sensitive to environment potential around the ion. Small percentage change in the potential around ion can reduce approximately 50% in the values of the polarisabilities. We also found that bulk nanocrystals have larger values of polarisabilities compared with their values in the bulk crystals. Calculations of these ionic properties of nanocrystal of our knowledge are being reported for the first time.