first-principles study of optical aspects of penta-graphene and t-carbon under external stress and hydrostatic pressure

In this study, we present two new carbon nano allotropes: penta-graphene and t-carbon. using first-principles calculations based on density functional theory (dft), we perform an extensive analysis of their crystalline structures. we delve into their optical properties, including a detailed assessment of the optical joint density of states and both the imaginary and real parts of the complex dielectric function. we also examine the reflectivity and absorption spectra to gain a full understanding of their optical characteristics. our study takes into account special scenarios, such as the effects of hydrostatic pressure and vertical compressive stress. the shifts in optical properties we observe correlate well with the electronic characteristics of these nanostructures. additionally, we explore the potential applications of these materials in various optoelectronic devices. thus, we suggest their use in creating advanced optoelectronic devices, particularly as sensors designed for specific conditions, due to their unique and tunable optical properties.