Abstract
Using density functional theory, we carefully calculated the relative stability of monolayer, few-layer, and cluster structures with Penta PdSe(2), T-phase PdSe(2), and Pd(2)Se(3)-phase. We found that the stability of Penta PdSe(2) increases with the number of layers. The Penta PdSe(2), T-phase PdSe(2), and Pd(2)Se(3) monolayers are all semiconducting, with band gaps of 1.77, 0.81, and 0.65 eV, respectively. The formation energy of palladium selenide clusters with different phase structures is calculated, considering the cluster size, stoichiometry, and chemical environment. Under typical experimental conditions, Pd(2)Se(3) phase clusters are found to be dominant, having the lowest formation energy among all of the phases considered, with this dominance increasing as cluster size grows. Adjusting the Pd-Se ratio in the environment allows for controlled synthesis of specific palladium selenide phases, providing theoretical insights into the nucleation mechanisms of PdSe(2) and other transition metal chalcogenides.