Phonon study of rhombohedral BS under high pressure

TL;DR

This study investigates the phonon behavior of rhombohedral boron monosulfide under high pressure using Raman and IR spectroscopy, complemented by theoretical calculations, revealing pressure effects and isotope substitution impacts.

Contribution

It provides a comprehensive experimental and theoretical analysis of phonon modes in rhombohedral BS under high pressure, including isotope effects, with no phase transition observed.

Findings

Raman bands shift to higher wavenumbers under pressure

All observed bands match theoretical calculations

Isotopic substitution affects Raman spectra

Abstract

Raman spectra of rhombohedral boron monosulfide (r-BS) were measured under pressures up to 34 GPa at room temperature. No pressure-induced structural phase transition was observed, while strong pressure shift of Raman bands towards higher wavenumbers has been revealed. IR spectroscopy as a complementary technique has been used in order to completely describe the phonon modes of r-BS. All experimentally observed bands have been compared with theoretically calculated ones and modes assignment has been performed. r-BS enriched by 10B isotope was synthesized, and the effect of boron isotopic substitution on Raman spectra was observed and analyzed.