Optical and Magnetic Excitations of Metal-Encapsulating Si Cages: A Systematic Study by Time-Dependent Density Functional Theory

Abstract

Systematic study of the optical and magnetic excitations of twelve MSi12 and four MSi10 transition metal encapsulating Si cages has been carried out by employing real time time-dependent density functional theory. Criteria for the choice of transition metals (M) are clusters stability, synthesizability, and diversity. It was found that both the optical absorption and the spin-susceptibility spectra are mainly determined by, in decreasing order of importance: 1) the cage shape, 2) the group in the Periodic Table M belongs to, and 3) the period of M in the Periodic Table. Cages with similar structures and metal species that are close to each other in the Periodic Table possess spectra sharing many similarities, e. g., the optical absorption spectra of the MSi12 (M = V, Nb, Ta, Cr, Mo, and W), which are highly symmetric and belong to groups 4 and 5 of the Periodic Table, all share a very distinctive peak at around 4 eV. In all cases, although some of the observed transitions are located at the Si skeleton of the cages, the transition metal specie is always significant for the optical absorption and the spin-susceptibility spectra. Our results provide finger-print data for identification of gas-phase MSi12 and MSi10 by optical absorption spectroscopy. arXiv:1309.5834v1 [physics.atm-clus]

Germanium-based superatom clusters as excess electron compounds with significant static and dynamic NLO response; a DFT study

“…40 The literature reveals that only conventional types of superalkali clusters are explored for optical and nonlinear optical studies however several models can be efficiently utilized to be used as nonlinear optical responses. Literature also reveals, there are several superatom clusters (silicon-based) encapsulated by transition metals which were also studied for optical and magnetic excitation 41,42 Zintl polyanions, discovered by Eduard zintl in 1930 belong to the group (14,15) and show excellent physicochemical stability. 43 It is previously reported that zintl P 7 3À anion as core material can be used to design organo-zintl superalkali clusters which contain superb electron properties.…”

“… 40 The literature reveals that only conventional types of superalkali clusters are explored for optical and nonlinear optical studies however several models can be efficiently utilized to be used as nonlinear optical responses. Literature also reveals, there are several superatom clusters (silicon-based) encapsulated by transition metals which were also studied for optical and magnetic excitation 41,42 …”

Switching Field Distribution in BN/FePtCAg/MgTiON and FePtCAg/MgTiOBN Films

“…The (σ axis ) was Gaussian fitting the FePt(001) rocking curve in Figure 1 c,d and the values are 5.14kOe and 3.69kOe for the respective reference and FePtCAg/MgTiOBN samples [ 13 ]. The (σ volume ) was obtained after fitting the magnetization reversal model in Equation (1) [ 14 ] and the values are 0.35 kOe and 0.73 kOe, respectively. 2M(H) = Erfc(x) …”

“…To explain this result, the interface diffusion which causes the composition fluctuation was evidenced in microstructural grains mapping and elemental binding in the surface spectra. The theoretical simulations by density function theory (DFT) calculations assist the understanding of the structure–morphology–property relations for complex nanostructured systems of a similar nature and a similar level of complexity (e.g., containing transition metal atoms) [ 14 , 15 , 16 ].…”

Unraveling the Structural, Dielectric, Magnetic, and Optical Characteristics of Nanostructured La2NiMnO6 Double Perovskites

“…In parallel with the experimental investigations of LNMO DP oxide, theoretical calculations by using the Density Functional Theory (DFT) are also performed to understand the structural, electronic, and magnetic properties of the LNMO [ 48 , 49 ]. In addition, theoretical simulations by DFT calculations also assist the understanding of the structure-property relations for complex nanostructured systems of similar nature and a similar level of complexity (e.g., containing transition metal atoms as well as a variety of lighter elements), which are directly supportive to the credibility of the physical mechanisms involved in complex nanostructured systems [ 50 , 51 , 52 ].…”