Photodissociation Spectra Of The Complex Mg～+-NCSCH₃ And Mg～+-S₂(CH₃)₂

Since the magnesium metal ions with gas phase state abundantly exist in the aerosphere of the earth and around the other planets, recently, there increasing attentions focused in Mg⁺ and complexes related with Mg⁺. In this dissertation, the photodissociation spectroscopy and dynamics action of complexes Mg⁺-NCSCH₃ and Mg⁺-S₂(CH₃)₂ within the 230 to 440 nm was investigated, combining by experiments and quantum theoretic computations.Photodissociation spectroscopy of the complexes Mg⁺-NCSCH₃ (Mg⁺-S₂(CH₃)₂) in the spectral region of 230-440nm was oberserved. As to Mg⁺-NCSCH₃ of photo-induced reaction, there were three channels. And there are the products Mg⁺ from nonreaction quenching and reactive products Mg⁺NC, Mg⁺NCS in the reaction throughout the whole wavelength range. The reactive products originate from the break of S-C chemical bonds. The Photodissociation spectrum consists of two broad peaks(250 and 366nm) corresponding to the atomic transition of Mg⁺(3²P← 3²S).As to Mg⁺-S₂(CH₃)₂ of photo-induced reaction,there were two channels. And there are the products Mg⁺ from nonreaction quenching and reactive product Mg⁺-SCH₃. The reactive product originates from the rupture of S-S chemical bonds. The photo-dissociation spectroscopy of Mg⁺-S₂(CH₃)₂ is made up of three broad peaks(264,318 and 330nm) corresponding to the atomic transition of Mg⁺(3²P←3²S). By analyzing, as to photodissociation spectroscopy of the complexes Mg⁺-NCSCH₃ (Mg⁺-S₂(CH₃)₂), these spectrums originate from the atomic transition of Mg⁺(3²P←3²S). In these complexes, owing to NCSCH₃ (S₂(CH₃)₂) molecule influence 3²P electronic state of Mg⁺, which results in the rupture of spectrums. Broad peaks of blue sides correspond to the atomic transition of Mg⁺(3²P←3²S), and broad peaks of red sides correspond to the atomic transition of Mg⁺(3²P_x,y← 3²S).By the B3LYP/6-31+G^**(B3LYP/6-311+G^**) method of density functional theory in quantum computation, the structures of complexes Mg⁺-NCSCH₃(Mg⁺-S₂(CH₃)₂) and the photo-fragments were optimized, and reactionenergy of each dissociation channel was calculated. According to the computation results, the dissociation channels of the complexes Mg+-NCSCH3 (Mg+-S2(CH3)2 ) observed in the experiments are reasonably explained, as well as the absorption spectrums by using CIS /6-31+G** (CIS /6-311+G**) method of quantum chemistry calculations agreed with the experimental spectrums very well.