Li Xibo, Chen Yuqi, Basnet Pradip, Luo Jiangshan, Wang Hongyan
Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics P. O. Box 919-987 Mianyang Sichuan 621999 China
School of Physical Science and Technology, Southwest Jiaotong University Chengdu Sichuan 610031 China
RSC Adv. 2019 Jan 8;9(2):1015-1028. doi: 10.1039/c8ra09240k. eCollection 2019 Jan 2.
A comprehensive investigation on the equilibrium geometry, relative stability, vibrational spectra, and magnetic and electronic properties of neutral tantalum clusters (Ta , = 2-17) was performed using density functional theory (DFT). We perform a study of the size dependence and correlations among those descriptors of parameters, and showed these could provide a novel way to confirm and predict experimental results. Some new isomer configurations that have never been reported before for tantalum clusters were found. The growth behaviors revealed that a compact geometrical growth route is preferred and develops a body-centered-cubic (BCC) structure with the cluster size increasing. The perfectly fitted functional curve, strong linear evolution, and obvious odd-even oscillation behavior proved their corresponding properties depended on the cluster size. Multiple demonstrations of the magic number were confirmed through the correlated relationships with the relative stability, including the second difference in energy, maximum hardness, and minimum polarizability. An inverse evolution trend between the energy gap and electric dipole moment and strong linear correlation between ionization potentials and polarizability indicated the strong correlation between the magnetic and electronic properties. Vibrational spectroscopy as a fingerprint was used to distinguish the ground state among the competitive geometrical isomers close in energy. The charge density difference isosurface, density of states, and molecular orbitals of selected representative clusters were analyzed to investigate the difference and evolutional trend of the relative stability and electronic structure. In addition, we first calculated the ionization potential and magnetic moment and compared these with the current available experimental data for tantalum clusters.
利用密度泛函理论（DFT）对中性钽团簇（Ta ，n = 2 - 17）的平衡几何结构、相对稳定性、振动光谱以及磁性和电子性质进行了全面研究。我们对这些参数描述符之间的尺寸依赖性和相关性进行了研究，并表明这些可以提供一种确认和预测实验结果的新方法。发现了一些钽团簇以前从未报道过的新异构体构型。生长行为表明，一种紧凑的几何生长路径是优选的，并且随着团簇尺寸的增加会形成体心立方（BCC）结构。完美拟合的函数曲线、强烈的线性演化以及明显的奇偶振荡行为证明了它们相应的性质取决于团簇尺寸。通过与相对稳定性的相关关系，包括能量的二阶差分、最大硬度和最小极化率，证实了幻数的多次表现。能隙和电偶极矩之间的反向演化趋势以及电离势和极化率之间的强线性相关性表明了磁性和电子性质之间的强相关性。振动光谱作为一种指纹被用于区分能量相近的竞争性几何异构体中的基态。对选定代表性团簇的电荷密度差等值面、态密度和分子轨道进行了分析，以研究相对稳定性和电子结构的差异及演化趋势。此外，我们首次计算了电离势和磁矩，并将这些结果与钽团簇目前可用的实验数据进行了比较。
