Heterocyclic Conjugated Aromatics Theory Of Weakly Interacting System

Based on the studies of electron transfer related problems and the weak-interactions between metal irons and the simplest fragrant five-member rings, such as Furan, Thiophene and Pirole, this paper mainly focuses on the follwing two parts: weak-interaction part and electron-transfer part.1 weak interaction1.1 Optimized geometry structures of simple molecules and weakly interacted complexes The most important problem of the studies on weakly interacted systems between molecules is to determine their geometry structures and structrual parameters,such as bond distance and bond angle, based on various calculation methods,especially on Density Functional Theory(DFT), a large number of basic sets have been used in this paper to make optimized calculations of the complexes formed by hetero-atomic ring and metals M(M=Li, Na, Mg, Al).Especially in the optimized calculations of five-member rings桭uran,Thiophene and Pirole, we have already formed that the structral parametes of the molecule and complexes are well confirmed with the experimental data.2.2 IR frequency Analysis of single molecule and weakly interacted complexes As we well know, although every kind of gaseous, liquid, solid complexes may have IR spectrum of themselves, it is experimentally difficult to determine the IR spectrum of weakly interacted complexes punctually. The theoretical calculation of this problem is becoming more and more wider and deeper with the more and more widly use of everykind of calculation program in theomretical chemistry. Based on GAUSSIAN94 calculation, this paper calculated and analysed the frequencies of Furan, Thiophene and Pirole, three kinds of hetero-atomic ring complexes and simple metal-organic complexes; the more reliable ER. data have been attained and then promoted the realization of this kind of weakly interacted complexes.2.3 Binding energy of reaction M + hetero atomic ring-- Mhetero atomic ring ]} Binding energy is an important rule of not only the stability of the weakly interacted system [M?hetero atomic ring ] complex, but of the binding enery between the metal Mand hetero atomic ring complexes. This paper mainly dealt with the binding energy data calculation of systems [Na桭uran], [Na桾hiophene], [Na桺irole], [M桭uran deviant](M=Li, Na and Al), and then proposed the quantity and quality of the stability of weakly interacted complexes.2 Electron transfer2.1 Activity energy of reaction system Activation energy of electron transfer,as one of the most important physical parameters, is affected by solubilization agent media as well as the nuclear configuration's variation of reactant and productant. Activity energy actually refers to the reaction systems energy variation ranged from initio state to transition state. To the heter-exchange reaction M+ + 62 ?[M桟>2]+ discussed in this paper, the quantity of activity energy is actually an essential rule to the reaction's rate of electorn transfer.2.2 Reorgnization energy The reorgnization of electron tranfer reaction, has close relations with activation, and energy effect is one of the important factors affecting the reaction mechanism of electron transfer.Precisely, reorgnization energy in fact refers to the energy difference between the energy of the newly formed productives and the enegy needed to come back to the equivalent state. In this paper, basic set B3LYP/6-31+G* have been used to calculate the reorganization energy of the hetero-exchange reaction M+ + O2-[M-O2]+, and determined the reorgnization parameters of this reaction's rate of electron transfer. 2.3 Rate of electron transfer Rate of ecectron tranfer is one of the important kinetic parameters of electron transfer. Based on the B3LYP/6-31+G* method and the equation k= Kd vexp(-Ea/RT), this paper studied the electron transfer process of hetero exchange reaction M+ + O2 -[M-O2]+(M=Na, AT), and its electron transfer rate.