Investigation of the stability and charge states of vacancy in clusters Si29 and Si38

Stability and charge states of vacancy in Si29 and Si38 clusters have been calculated by non-conventional tight-binding method and molecular dynamics. Based on the theoretical calculations, it was shown that the vacancy in pure dimerized clusters is unstable, while in hydrogenated Si29H24 and Si38H30 clusters it is stable, but leads to a distortion of its central part with the transition of symmetry from Td to C3v and a change in the forbidden gap. The charges of cluster atoms in the presence of a vacancy are distributed so that all silicon atoms acquire a stable negative charge, which occurs due to the outflow of electrons of the central atom to the neighboring spheres.