Nonequilibrium quantum chemical molecular dynamics simulations of C60 to SiC heterofullerene conversion

Abstract

Nonequilibrium high-temperature quantum chemical molecular dynamics simulations based on the self-consistent-charge density-functional tight-binding (DFTB) method for the conversion of C 60 to SiC fullerene by way of periodic Si atom supply are presented. Random supply of Si atoms on the surface of a perfect I h-C 60 buckminsterfullerene without simultaneous carbon atom removal merely leads to formation of an exohedrally adsorbed Si cluster during the entire length of our simulations via an Ostwald ripening process, whereas supply of Si atoms in combination with simultaneous carbon atom removal affords the formation of SiC fullerene structures up to a lower limit of 2:1 for the C:Si ratio. Our simulations demonstrate the importance of vacancy defects for atomic substitution-based approaches for heterofullerene cages, and hint at inherent difficulties of such approaches for the actual synthesis of hypothetical, idealized sp 2-hybridized SiC nanostructures with a 1:1 ratio featuring fully alternating atomic structures and no Si-Si and CC bonds.

Self-Consistent Charge Density Functional Tight-Binding Study of Poly(3,4-ethylenedioxythiophene): Poly(styrenesulfonate) Ammonia Gas Sensor

“…It should be noted that the SCC-DFTB method was derived from DFT by neglect, approximation, and parametrization of interaction integrals. It offers several advantages including rapid computation of large scale molecular systems (several thousands of atoms), reliable description of dispersions and weak interactions (Van der Waals and H-bonding), and good prediction for properties (geometry, electronics, and binding energies) [ 26 – 28 ]. Moreover, the SCC-DFTB method was used for investigation of NH 3 adsorption on sensing material, which is consistent with experimental observations [ 29 ].…”

Possible mechanism of BN fullerene formation from a boron cluster: Density‐functional tight‐binding molecular dynamics simulations

“…QM/MD simulations based on the DFTB method have been applied to a variety of self‐organization processes in cluster systems. Examples include carbon fullerene formation from C 2 molecules and open‐ended carbon nanotubes, growth of a carbon nanotube from a catalytic metal cluster, carbon cap nucleation on a catalytic metal cluster, and C 60 to SiC heterofullerene conversion . Because the DFTB method has been applied to the energetics and structure of cluster and bulk BN systems, we expect that the DFTB QM/MD method is also suitable for describing nonequilibrium processes in BN systems.…”

Structures, Electronic Properties, and Gas Permeability of 3D Pillared Silicon Carbide Nanostructures

“…It should be noted that SCC-DFTB can predict structures, electronic properties, and energies in excellent agreement with DFT methods as well as faster calculation time more than ~100–1000 times [ 34 , 35 , 36 ]. Moreover, the results obtained by SCC-DFTB were consistent with experimental observations [ 37 , 38 , 39 ].…”