Gao Xiao-Feng, Liu Guang-Hui, Hu Xian-Kai, Chen Lan-Li, Zhu Ben-Chao, Zheng Ding-Shan, Liao Yan-Hua
School of Mathematics and Physics, Hubei Polytechnic University, Huangshi 435003, People's Republic of China.
School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, People's Republic of China.
ACS Omega. 2023 Oct 24;8(44):41391-41401. doi: 10.1021/acsomega.3c05113. eCollection 2023 Nov 7.
Gas-phase NbMg ( = 2-12) clusters were fully searched by CALYPSO software, and then the low-energy isomers were further optimized and calculated under DFT. It is shown that the three lowest energy isomers of NbMg ( = 3-12) at each size are grown from two seed structures, i.e., tetrahedral and pentahedral structures, and the transition size occurs at the NbMg cluster. Interestingly, the relative stability calculations of the NbMg cluster ground-state isomer stand out under the examination of several parameters' calculations. The charge-transfer properties of the clusters of the ground-state isomers of various sizes had been comprehensively investigated. In order to be able to provide data guidance for future experimental probing of these ground-state clusters, this work also predicted infrared and Raman spectra at the same level of theoretical calculations. The results show that the multipeak nature of the IR and Raman spectra predicts that it is difficult to distinguish them directly. Finally, the optical properties of these clusters were investigated by calculating the static linear, second-order nonlinear, and third-order nonlinear coefficients. Importantly and interestingly, the NbMg cluster was shown to have superior nonlinear optical characteristics to all other clusters; thus, it is a powerful candidate for a potentially ultrasensitive nonlinear optical response device for some special purpose.
利用CALYPSO软件对气相NbMg（(n = 2 - 12)）团簇进行了全面搜索，然后在密度泛函理论（DFT）下对低能量异构体进行了进一步优化和计算。结果表明，每个尺寸下NbMg（(n = 3 - 12)）的三个最低能量异构体均由两种种子结构生长而来，即四面体和五面体结构，且转变尺寸出现在NbMg团簇处。有趣的是，在几个参数计算的检验下，NbMg团簇基态异构体的相对稳定性计算结果较为突出。对各种尺寸基态异构体团簇的电荷转移性质进行了全面研究。为了能够为未来对这些基态团簇的实验探测提供数据指导，本工作还在相同理论计算水平下预测了红外和拉曼光谱。结果表明，红外和拉曼光谱的多峰性质预示着难以直接区分它们。最后，通过计算静态线性、二阶非线性和三阶非线性系数研究了这些团簇的光学性质。重要且有趣的是，NbMg团簇表现出比所有其他团簇更优异的非线性光学特性；因此，它是一种用于某些特殊目的潜在超灵敏非线性光学响应器件的有力候选材料。
