Stability and magnetic properties of isomorphous substituted Si7-xMnx+

Abstract

The optimized geometries, stability, and magnetic properties of cationic clusters Si₇⁺, Si₆Mn⁺, and Si₅Mn₂⁺ have been determined by the method of density functional theory using the B3P86/6-311+G(d) functional/basis set. Their electronic configurations have been analyzed to understand the influence of substituting Si atoms by Mn atoms on the structural and magnetic aspects of Si₇⁺. It is shown that the manganese dopant does not alter the structure of the silicon host but significantly changes its stability and magnetism. In particular, while the magnetic moment of Si₇⁺ is 1 m_B, Si₅Mn₂⁺ exhibits a strong magnetic moment of 9 m_B and that of Si₆Mn⁺ takes a relatively high value of 4 m_B. Among studied clusters, the pentagonal bipyramid Si₅Mn₂⁺is assigned as the most stable one.