Study on the physical properties of pyrrole molecules under external field
Pyrrole molecules are important organic semiconductor materials,they are suitable for many fields such as microelectronics and optoelectronics,and have successfully led a new technological revolution.The pa-per is based on density functional theory,the B3LYP/6-311++g(d,p)method is used to study the change laws of the physical properties of pyrrole molecules under the action of electric field strength of 0-0.03 a.u..It is found that with the increase of the electric field,the molecule is gradually compressed along the x-axis direc-tion,the dipole moment of the molecule decreases,and the total energy decreases.The highest occupied molecu-lar orbitals energy of the molecule remains unchanged,the lowest unoccupied molecular orbital energy is continu-ously decreased.As a result,the energy band gap of the molecule is continuously reduced,and the stability of the energy band gap cannot be guaranteed,thereby the service life of the semiconductor material is reduced.Through the time dependent density functional calculation,it can be concluded that under different electric fields two ultraviolet absorption peaks appear in pyrrole molecules,in which the π-π*transition of the two C=C double bonds accounts for the main contribution.But with the increase of the electric field strength,its propor-tion in the transition becomes smaller and smaller.It is investigated that under the electric field of 0.02 a.u.,the ultraviolet absorption peaks are mainly determined by the 6th,11th,13th and 15th excited states.These pro-vide a good theoretical basis for better research and design of semiconductor materials.
PyrroleExternal electric fieldDensity functional theoryFrontier orbits
国家科技期刊平台
NSTL
万方数据
维普
