The Study On The Structure And Property Of Ce Doped Silicon Clusters

As an interdisciplinary of physics, chemistry, and material, clusters has already become a hot research field, and as a good semiconductor material, the clusters of silicon will attract more attention of the scholars. Cerium is an typical light rare earth metal, the structure and properties will be changed after doped Si clusters. On the previous research, used B3 LYP of density functional theory combined with the small core ECP28 MWB basis sets which frozen outer layer 28 electronic, took the difference of the initial structure and electronic multiplicity into consideration, this paper made a systematic study of Ce Sin(0,-1)(n=1~10), obtained the ground state structure, its average binding energy, second order difference and dissociation energy, the adiabatic electron affinity, natural charge distribution and magnetic moments of the Ce Sin is also researched in this paper.The ground state structure of Ce Sin is calculated on the foundation of B3LYP/ ECP28 MWB, respectively C∞v(5Π), C2v(3B1), C2v(3B1), Cs(3A′), Cs(3A′′), Cs(3A′), C1(3A), C2v(3B1), Cs(3A′), C1(3A) of neutral Ce Sin(n=1-10), C∞v(2Π), C2v(2A2), C1(4A), Cs(2A′′), Cs(2A′′), Cs(2A′), Cs(2A), C1(2A), C2v(2B1), C1(2A) of anions Ce Sin-(n=1-10), then the growth rule of the Ce Sin cluster is analyzed. Average binding energy, energy difference and dissociation energy of the Ce Sin is obtained to analyze its stability of the ground state. The result shows that the stability of the Ce Sin is improved when the Ce is doped. And Ce Si2,Ce Si5 with Ce Si8 is more stable than others. The Ce Sin(n=1~10) clusters of adiabatic electron affinity is also calculated, respectively 0.81 e V(Ce Si1), 0.48 e V(Ce Si2), 1.23 e V(Ce Si3), 1.39 e V(Ce Si4), 1.74 e V(Ce Si5), 1.89 e V(Ce Si6), 2.28 e V(Ce Si7), 2.20 e V(Ce Si8), 2.64 e V(Ce Si9), 2.36 e V(Ce Si10). In addition, the electron configuration, dipole moment of anionic and neutral, the magnetic moment of neutral is figured out by means of NPA. The result indicate that the charge transfers from silicon clusters to Ce atom with the exception of Ce Si-,in which the Ce atom acts as electron donor. For the dipole moment calculated, the biggest is 12.22D(Ce Si9-), the minimum is 4.13D(Ce Si) and 4.68D(Ce Si-). To the magnetic moment of Ce Sin, total magnetic moment is 2μB except for Ce Si, which is 4μB. According to local magnetic moment of the Ce atoms, total magnetic moment of the Ce Sin clusters is provided by Ce atoms. Therefore the Ce atom doping turns into an inducement to make nonmagnetic pure silicon clusters produce magnetism after doped.