Structures and Stability of Th(N_(6)),Pa(N_(6)),and U(N_(6))

摘要

The cyclo-N_(6)anion is a total nitrogen unit with higher nitrogen content than cyclo-N^(-)_(5).However,the low decomposition barrier of cyclo-N_(6)anions hinders its application as a high energy density material(HEDM).Using first-principles calculations,we reveal that the covalent components that enhance the interaction between the cyclo-N_(6)anion and the cation can effectively improve the stability of cyclo-N_(6)anions.The actinide metals(Th,Pa,U)are selected as suitable cations.Further electronic structure analysis showed that the charge transfer from the actinide metal to cyclo-N_(6)anions resulted in a strong covalent bond,which promoted the stability of the cyclo-N_(6)anion in the Th(N_(6)),Pa(N_(6)),and U(N_(6))structure.This discovery is helpful for the rational design and synthesis of new HEDMs.