甲基乙烯基硅酮在外场作用下的光激发特性研究

采用密度泛函B3P86和组态相互作用方法在6-311++G^**基组水平上计算了甲基乙烯基硅酮分子从基态到前10个激发态的跃迁波长，振子强度，自发辐射系数A_n0和吸收系数B_0n(n＝1—10).同时研究了外电场对甲基乙烯基硅酮分子激发态的影响规律.结果表明，随外电场强度增大，最高占据轨道与最低空轨道能隙变小，激发能随电场增加而急剧减小.因而表明在外电场作用下，分子易于激发和关键词：甲基乙烯基硅酮激发态外电场

Effect of external electric field excitation on methyl vinyl siloxane

The present paper is devoted to the calculation of transition wavelengths, oscillator strength f, Einstein A_n0 and B_0n coefficients of methyl vinyl siloxane from ground state C_s(X¹A′) to the first ten different excited states by employing density functional theory and single substitute configuration interaction approach with basis sets 6-311++G^**. At the same time, the excited states of methyl vinyl siloxane under different external electric fields are investigated. It is shown that the HOMO-LUMO gaps become smaller, and the excitation energies of the first ten excited states of methyl vinyl siloxane decrease sharply as the external electric field intensity become strong. The conclusion can be drawn that the transition between the ground state X¹A′ and the excited state of methyl vinyl siloxane is easy to bring about.