We have carried out density functional theory calculation to study the evolution of geometric, energetic and electronic properties of Mg_n (n = 2–10) clusters. The dispersion corrected ωB97X-D functional is found to be more efficient over the B3LYP + D3 method in determination of accurate structure and energetics of the gas phase small Mg_n clusters. We have found that Mg₄ possesses the smallest possible three-dimensional geometry and is the most stable cluster among the Mg_n clusters studied here. We have therefore selected Mg₄ cluster as a host for the doping of 3d transition metal (TM) atom to study the structural, electronic and magnetic properties of these TMMg₃^0,+ clusters. MnMg₃ and NiMg₃⁺ clusters are found to be the most stable neutral and cationic TMMg₃ clusters, respectively. The NBO and DOS analyses have shown that the stability of the TMMg₃^0,+ clusters is governed by the charge transfer processes as well as the nature of interaction of the atomic orbitals. These studies also confirm that the neutral doped clusters exhibit covalent-like bonding while ionic type bonding is present in cationic clusters. Larger charge gains by the charge deficient TM cations from the Mg atoms in TMMg₃⁺ make them relatively stable over the neutral clusters. The DOS and molecular orbital analyses reveal that the 3d orbitals of the dopant TM atoms actively participate in electronic charge transfer processes by maintaining their individuality in TMMg₃ clusters, whereas they remain silent in this regard in case of TMMg₃⁺ clusters. In both these cases, the TM^0,+(3d) orbitals play the crucial role of tuning the magnetic moment. Therefore, the overall electronic structure and properties of TMMg₃^0,+ clusters depend solely on the TM(3d) orbitals, which is governed by the charge transfer processes characterized by the charge state of the cluster.

Graphical abstract

我们已经进行了密度泛函理论计算，以研究Mg _n（n  = 2-10）团簇的几何，能量和电子性质的演化。校正后的分散ω B97X-d功能被发现是在B3LYP + D3方法更有效地在判定准确结构和气相小的Mg的能量学_Ñ簇。我们发现，Mg ₄具有最小的三维几何形状，并且是此处研究的Mg _n团簇中最稳定的团簇。因此，我们选择了Mg ₄团簇作为3 d掺杂的主体过渡金属（TM）原子，以研究这些TMMg ₃ ^0，+团簇的结构，电子和磁性。MnMg ₃和NiMg ₃ ⁺簇分别是最稳定的中性和阳离子TMMg ₃簇。NBO和DOS分析表明，TMMg ₃ ^0，+团簇的稳定性由电荷转移过程以及原子轨道相互作用的性质决定。这些研究还证实，中性掺杂的团簇表现出类似共价键的结合，而阳离子型团簇中存在离子型结合。来自TMMg ₃ ^+中Mg原子的电荷不足的TM阳离子可产生更大的电荷增益使它们在中性星团上相对稳定。DOS和分子轨道分析表明，掺杂剂TM原子的3d轨道通过保持其在TMMg ₃簇中的个性而积极参与电子电荷转移过程，而在TMMg ₃ ⁺簇的情况下，它们在这方面保持沉默。在这两种情况下，TM ^0，+（3d）轨道都起着调节磁矩的关键作用。因此，TMMg ₃ ^0，+团簇的整体电子结构和性质仅取决于TM（3d）轨道，它由以簇的电荷状态为特征的电荷转移过程控制。

图形概要