Computational Study on Potassium Picrate Crystal

摘要

DFT calculation at the B3LYP level was performed on crystalline potassium picrate.The frontier bands are slightly fluctuant.The energy gap between the highest occupied crystal orbital (HOCO) and the lowest unoccupied crystal orbital (LUCO) is 0.121 a.u.(3.29 eV).The carbon atoms that are connected with the nitro groups make up the narrow lower energy bands,with small contributions from nitro oxygen and phenol oxygen.The higher energy bands consist of orbitals from the nitro groups and carbon atom.The potassium bears almost 1 a.u.positive charge.The potassium forms ionic bonding with the phenol oxygen and the nitro oxygen at the same time.The crystal lattice energy is predicted to be-574.40 kJ/mol at the B3LYP level determined with the effective core pseudopotential HAYWSC-31G basis set for potassium and 6-31G basis set for other atoms.