摘要
采用密度泛函(DFT)B3PW91方法在Lanl2dz基组下优化得到Cd Se分子的基态稳定构型,并研究了外电场对Cd Se基态分子的总能量、HOMO能级、LUMO能级、能隙、电偶极矩μ、电荷布居、红外光谱的影响.在相同的基组下用TD-DFT方法计算了外电场下Cd Se分子的前9个激发态的激发能、激发波长和振子强度.结果表明:无电场时Cd Se分子的激发波长与实验结果符合较好,相应的激发能也很接近.随着电场增加,Cd Se基态分子键长、偶极矩、红外谱强度先减小后增大;HOMO能级、LUMO能级、能隙随电场增加而减小;总能量、谐振频率则是先增大后减小.此外,外电场对Cd Se分子的激发能,激发波长和振子强度均有较大影响.
Density functional theoretical（B3PW91） method with LANL2 DZ basis sets has been used to study the equilibrium structure, total energy, the highest occupied molecular orbital（HOMO） energy level, the lowest unoccupied molecular orbital（LUMO） energy level, energy gap, dipole moment, atomic charge distribution, infrared intensities of Cd Se ground state molecule etc. in different intense electric fields. The excitation energy, wavelengths and oscillator strengths in ground state and the first nine different excited states are investigated by the time-dependent density functional（B3PW91） method in external electric fields. Results show that the excitation wavelength is in agreement with the experimental result and the excitation energy is close to the experimental data. With the increase of the external field,the bond length, electric dipole moment, infrared intensities are observed to decrease first, and increase afterwards. But the HOMO energy, LUMO energy, energy gap are seen to decrease. And the total energy and harmonic frequency are found to increase first, and then decrease. In addition, the external electric fields have significant effects on the excitation energy, wavelength and oscillator strengths of Cd Se molecule.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第15期55-61,共7页
Acta Physica Sinica
基金
国家自然科学基金(批准号:11364007)
贵州省教育厅自然科学基金(批准号:黔教合KY字(2012)051号)
贵州省科学技术基金(批准号:黔科合J字[2013]2219号)资助的课题~~
关键词
密度泛函理论
Cd
Se
外电场
光谱特性
density functional theoretical
Cd Se
external electric fields
spectral properties
