Magnetic solution in Ta-doped monoclinic HfO2

M.A. TAYLOR; R. E. ALONSO; L. ERRICO; A. LÓPEZ GARCÍA; A. SVANE; N. CHRISTENSEN

Argentina

Workshop; III Workshop on Novel Methods for Electronic Structure Calculations; 2009

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES-AR; mso-fareast-language:ES-AR;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Previous studies of the electronic and structural properties of pure an Ta- doped monoclinic HfO2 have been done by means of ab initio density functional calculations and resulted in good agreement with experimental results concerning the electrical field gradient (EFG). Nevertheless, the results of different experiments suggest that, besides the most populated site for the Ta-probe atom used in Perturbed Angular Correlation (PAC) spectroscopy, there should be other low populated sites which in general are not extensibility analyzed. In this work, we study different charge states for the impurity-probe atom leading to different solutions to electronic wave function. Between these, the neutral cell calculation results in a static EFG compatible with the low populated site mentioned above. This solution results in a magnetic cell with a magnetic moment close to 1 Bohr magneton