Electronic Structures And Spectroscopic Properties Of Nitrido-osmium And Dioxo/Mono-osmium Complexes: Quantum Theoretical Studies

This thesis uses configuration interaction (CI) method to study the electronic structures and spectroscopic properties of the excited state of transition metal complex. Ground state electronic structures were calculated by B3LYP method. According to the electron spectroscopic theory of vertical transition method, with the geometry structure of the ground state unchanged, the excited state calculated by the configuration interaction (CI) method correspond to the vertical absorption of the system. Presumed that the ground state of the system is a singlet state, with the stable geometry structure of the excited triplet state unchanged, the transition spectra from excited state to ground state corresponds to the phosphorus emission of the system. The excited states were calculated by the single excitation configuration interaction (CIS) method and the spectra were obtained using TD-DFT method. By analyzing the composition, symmetry and electronic distribution of the molecular orbital calculated for the ground state and excited state, we had the transition properties of the molecular orbital. By analyzing normal bond orbital population,we obtained the electronic transition properties of the absorption and emission spectra quantitatively. Using the above mentioned methods, we studied the...