摘要: | 本計算主題是以B3LYP/6-311++G(3df)層級,去研究鹼土族金屬原子(Alkaline Earth Atom, AEM) (Be~Ca)吸附在小型矽團簇(Si10)上之最佳穩定的狀態,並探討其金屬複合團簇的結構之鍵長、結合能(Binding energy, BE)、吸附能(Ead)、電子轉移、能隙(Band gap)。本論文也有比較鹼土族金屬複合團簇(AEM-Si10)在單重態及三重態的結構和能量的差異。
我們發現AEM-Si10在不同自旋態下所形成的異構物也不完全相同,單重態的AEM-Si10較為穩定。由計算結果顯示在AEM-Si10中Be與Si主要是以共價鍵鍵結,而Ca與Si主要是以離子鍵鍵結。Be、Mg、Ca吸附在小型矽團簇(Si10)上的最穩定產物其結合能均大於4.0 eV,但鎂原子對矽團簇(Si10)的吸附能卻比Be或Ca小了許多,而Be的能隙(Band Gap)普遍較Mg或Ca大。
The topic of this computational research focused on several alkaline earth metal (AEM, Be~Ca) atoms adsorbed on Si10 Silicon cluster at the B3LYP/6-311++G(3df) level. We obtained the structures of the lowest-energy hybrid clusters and then investigated their corresponding geometries, binding energies (BE), adsorption energies (Ead), charge distributions, and band gaps. We also discussed the energy difference for alkaline earth metal hybrid clusters (AEM-Si10) between singlet and triplet states.
We found also that the calculated AEM-Si10 isomers with varied spin multiplicities clearly revealing different behaviors, and the AEM-Si10 isomer with singlet state is more stable. From our calculated results, it is found that the formation of Be-Si bond is majorly through covalent bond, and the Ca-Si counterpart is mainly bound by ionic bond. The binding energies of the more stable products of Be, Mg and Ca adsorbed on small Silicon cluster (Si10) are all higher than 4.0 eV, but the adsorption energy of Mg atom adsorbed on Si10 cluster is small than Be and Ca. Besides, the energy band gap of Be-Si10 is higher than Mg-Si10 and Ca-Si10 counterparts. |