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In this paper, Amsterdam Density Functional (ADF) methods, systems studied in of Aln 1 (n = 1-9) the structure of the ground state doped Zn, Ni and Cu in three transition metal atom (s) after the structural stability of the resultant clusters of small aluminum-doped on the doped clusters physical characteristics of a comprehensive study. ADF method is based on the under first-principles density functional theory, is internationally recognized advanced theoretical calculation method is widely used in the field of materials science, in addition to the usual exchange - related functional, it also provides a lot of the forefront of the XC energy functional and potential energy, such as rneta-GGA, hybrid exchange - correlation function and SAOP and the GRAC progressive XC potential. It uses a linear scale and parallel technology can handle hundreds of thousands of atoms system (generally organic compounds containing light elements), the calculation is very efficient. First, we use first-principles density functional theory of doped zinc atoms Aln 1 (n = 1-9) clusters structure, stability, and magnetic study. The calculation results show AlnZn (n = 1-9) clusters ground state structure by replacing a Zn atom optimization resulting in Aln 1 (n = 1-9) ground state structure. Due to the different atomic radii and bonding characteristics, adding dopant atoms lead to local distorted structure of doped aluminum clusters. The cluster performance Al3Zn and Al7Zn good stability. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy gap between the Eg values, with the increase of the number of clusters atoms, cyclical oscillating trend. Meanwhile, we also studied the magnetic properties of the doped clusters, found the clusters of Al4Zn, Al6Zn and Al8Zn has an even number of electrons, the total magnetic moment of the clusters for 0.0μB structure does not have a magnetic AlZn, Al5Zn, Al7Zn and Al9Zn has a unpaired electron, cluster moment 1.0μB. In addition, we are surprised to discover that Al2Zn, and Al3Zn clusters has 2.0 and 3.0μB of magnetic moments, the magnetic moments occurs mainly in the the doped zinc atoms and sp-d orbital hybridization. Secondly, we study the AlnNi (n = 1-9) clusters. Found that compared with the adjacent clusters, AlNi Al2Ni and Al7Ni clusters showed very good stability. Compared with the corresponding pure Aln 1 (n = 1-9) clusters, the dopant atoms Ni led the local distortion of the cluster structure, the distortion decreased gradually with increasing cluster size, but doping a certain degree of symmetry of the original structure is destroyed. At the same time, we also study the clusters of magnetic AlnNi (n = 1-9). Electronic under the joint action of the 3d orbital of Al atom 3p orbital and Ni atoms, the 3p orbit on two electron spin parallel upwardly Al4Ni clusters, similarly Al6Ni clusters two electron spin direction of the same, these two electronic spin is not paired, resulting in two clusters has the magnetic moment of 2.0, while other clusters not have a magnetic moment. In addition, we also AlnCu (n = 1-9) doped clusters geometry optimization, the ground state of the cluster structure is found compared with the adjacent clusters, the AlCu, and Al7Cu cluster performance a very good stability, but as compared with the corresponding pure Aln 1 (n = 1-9) clusters, the structural symmetry of the clusters is destroyed, resulting in clusters having a large electric dipole moment. At the same time, we also study the clusters of magnetic AlnCu (n = 1-9). Calculated that Cu atoms substitute Al atoms in the pure aluminum clusters, the clusters are part of the charge transfer from the Al atoms to the Cu atoms clusters of AlCu, Al3Cu, Al5Cu, Al7Cu and Al9Cu, the total electronic are even number, the molecular orbital of the clusters all electrons are spin paired, so the total magnetic moment of the clusters 0.0μB; while Al2Cu, Al4Cu, Al6Cu, and Al8Cu Clusters, the total number of electrons is an odd number, Al atoms a 3p molecular orbital electron, the spin is not paired, which has 1.0μB total magnetic moment. Thus, although the transfer of charge as well as the magnetic moments of the changes in clusters internal, but clusters overall magnetic moment is not changed, after doping clusters still does not have magnetic properties.
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