Detection of Multiconfigurational States of Hydrogen-Passivated Silicene Nanoclusters

Abstract

Utilizing density functional theory (DFT) and a complete active space self-consistent field (CASSCF) approach,we study the electronic properties of rectangular silicene nano clusters with hydrogen passivated edges denoted by H-SiNCs (n,n), with n and n representing the zigzag and armchair directions, respectively. The results show that in the n direction, the H-SiNCs prefer to be in a singlet (S = 0) ground state for n > n. However, a transition from a singlet (S = 0) to a triplet (S = 1) ground state is revealed for n > n. Through the calculated Raman spectrum, the S = 0 and S = 1 ground states can be observed by the E (G) and A (D) Raman modes. Furthermore, H-SiNC clusters are shown to have HOMO-LUMO (HL) energy gaps, which decrease as a function of n and n for S = 0 and S = 1 states. The H-SiNC with a S = 1 ground state can be potentially used for silicene-based spintronic devices.

Exploring Low Internal Reorganization Energies for Silicene Nanoclusters

“…We also ran complete active-space self-consistent field (CASSCF) calculations of the charged molecules of the corresponding electronic multiplicity also using the B3LYP functional to explore their multi-configurational character. This is due to correct and compare, if needed, for the multi-configurational character of the neutral H-SiNCs reported in a previous study [8] at the B3LYP level of theory. The chosen active spaces consisted of 9 electrons and 10 orbitals, and 11 electrons and 10 orbitals, for cation and anion radicals, respectively.…”

In Silico Modelling: Electronic Properties of Phosphorene Monoflakes and Biflakes Substituted With Al, Si, and S Heteroatoms

“…The geometry optimizations and properties calculations were performed using D3BJ dispersion-corrected TPSS in combination with def2-SVP basis set in Turbomole v7.3 25 and Gaussian 16 revision A3 26 codes. In previous studies, 27 it was demonstrated that the basis set def2-SVP yields good results for this kind of system without compromising the computational cost. The frequency calculates were run for all studied systems to ensure that a minimum (no imaginary frequencies) have been located.…”

Oligomeric approach to 2D materials modeling

“…Other elements such as silicon and phosphorus are also known to form 2D structures, therefore, the electronic properties of rectangular silicene nano clusters (nanoflakes) with hydrogen passivated edges with two zigzag and two armchair edges have been explored (Pablo-Pedro et al, 2017).…”