DNA condensation and size effects of DNA condensation agent

摘要

We investigate the structural and elastic properties of hexagonal Ce_2O_3 under pressure using LDA+U scheme in the frame of density functional theory (DFT). The obtained lattice constants and bulk modulus agree well with the available experimental and other theoretical data. The pressure dependences of normalized lattice parameters a/a_0 and c/c_0, ratio c/a, and normalized primitive volume V/V_0 of Ce_2O_3 are obtained. Moreover, the pressure dependences of elastic properties and three anisotropies of elastic waves of Ce_2O_3 are investigated for the first time. We find that the negative value of C_(44) is indicative of the structural instability of the hexagonal structure Ce_2O_3 at zero temperature and 30 GPa. Finally, the density of states (DOS) of Ce_2O_3 under pressure is investigated.