Theoretical Study on the Structures and Stability of SiC3P Isomers

Abstract

Various levels of calculations are applied to obtain the structures, energies, dipole moments, vibrational spectra, rotational constants, and isomerization of SiC3P species. A total of 27 minima which are connected by 40 interconversion transition states on the potential energy surface are located at the DFT/B3LYP/6-311G(d) level. The global minimum is found to be a linear SiCCCP of the 2Π electronic state. Besides the three-membered-ring isomer CC-cCPSi (36.2 kcal/mol), the four-membered-ring isomers P-cCCCSi (31.2 kcal/mol) and P-cSiCCC (79.1 kcal/mol), the five-membered-ring isomer cCPCCSi (46.6 kcal/mol), and the cagelike isomer pPSiCCC (56.8 kcal/mol) also possess great kinetic stability (more than 10.0 kcal/mol). The bonding natures of the relevant species are analyzed. The calculated results may be helpful for understanding the P-doped SiC vaporization process. The structures, energies, and bonding properties of the relevant species are compared with those of the SiC2N, SiC2P, and SiC3N analogues.