A senior thesis submitted to the faculty of Brigham Young University - Idaho in partial fulfillment of the requirements for the degree of Bachelor of Science
Abstract:
This project focuses on finding the transition pressures of the ground state (T = 0 K) of dense lithium for solid-solid phase transitions. The Vienna Ab initio Software Package (VASP) was used to run Density Functional Theory (DFT) calculations on each lattice structure. The process was repeated for a range of increased and decreased volumes of the unit cell. Once the resulting total energies of the lattices were found, a common tangent construction between structures on a free energy vs. volume graph visually represented the tran- sition pressures. The transition pressures at the ground state correlate well with experiments at slightly higher temperatures and the predictions made by Guillame et al. in 2011. Additional work should focus on higher pressure solid phases to determine if DFT continues to give good results.