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The related energy and multi-channel CHONH2 degradation reaction potential energy surface under the catalysis of Aux (x=0, 1, 2, 3) cluster was studied, while its dynamic characterization has been investigated with density functional calculations. The geometries were fully optimized with the CCSD(T)//B3PW91 level. We can conclude two results: [1] The calculated results shown that the main pathway of the CHONH2 degradation reaction under the catalysis of Aux (x=0, 1, 2, 3) cluster can give the main product P1 (CO+NH3), while the minor product is P1(H2+HNCO) and P3 (H2O+HNC). We calculated the rate constant of the main reaction pathway, the calculated dynamic characterization indicating that the rate constants have the positive temperature dependence. According to the dynamic results and the energetically intermediates and transition states involved in the dominant paths, the reaction is expected to be occurred the most rapidly under the catalysis of Au2. [2] From the PESs, we can see the present invention, the singlet atom is the best catalysis and can catalyze the reaction better. The present invention studies may provide useful information on the issues of the reaction mechanism and product distributions. Abbreviations: NBO: Natural Bond Orbital; ED: Electron Density; DFT: Density Functional Theory; PES: Potential Energy Surface; RECP: Relativistic Effective Core Potential; IRC: Intrinsic Reaction Coordinate; SCT: Small Curvature Tunnel Effect Correction Biomedical Journal of Scientific & Technical Research Cite this article: Hongxia Liu, Zizhong Liu. Kinetics Study The Catalyze Mode Of The Formamide Degradation Reaction By Aux Cluster (X=0, 1, 2, 3): Point, Line Or Surface?. Biomed J Sci&Tech Res 10(5)-2018. BJSTR. MS.ID.002024. DOI: 10.26717/ BJSTR.2018.10.002024. Volume 10Issue 5: 2018 8153 intermediates and transition states. This valuable information can shed light on reaction mechanisms, and ab initio calculations have been applied to several unimolecular reactions. For complex bond-breaking reactions, information about the transition states is required to test the experimental results. In the past two decades, the power of computational hardware, software gradually increased and therefore theoretical calculations became more and more popular and important to investigate structures, stabilities and activities of catalysts. calculation relies only on the electron density, which significantly decreases the computational complexities. It becomes an increasingly powerful and useful tool to evaluate various systems, predict catalytic activities, and provide enough accuracy to be compared to experimental data [26]. So far, DFT calculation was widely used to investigate the mechanism of gold catalysis and provide fundamental physical insights into gold catalysis [17,27-28]. For example, selfconsistent density functional calculations showing that an isolated Au10 cluster should be able to catalyze the CO oxidation reaction even below room temperature and to use calculations can analyze the origin of this effect and suggest that the extraordinary reactivity can be traced back to special reaction geometries available at small particles in combination with an enhanced ability of low coordinated gold atoms to interact with molecules from the surroundings [17,18]. Based on the molecular orbital analysis and the DFT calculations, we have discussed the redistribution of in various bonding and antibonding orbitals and the energy of hyper conjugative interaction stabilization energy (E(2)) which have been calculated by natural bond orbital (NBO)[29] analysis using DFT method to give clear evidence of stabilization originating from the hyperconjugation of various intramolecular interactions. The calculations are valuable for providing a reliable insight into the molecular properties. In this work, we will give a brief review of theoretical investigations on CHONH2 degradation reaction catalyzed by Aux (x=0, 1, 2, 3) cluster, since most of the reviews focused on experimental results and the reviews of theoretical work were relatively rare. No major products are given and there is no available information on product channels, product distributions, and the reaction mechanism in the experiment. Considering the potential importance and the rather limited information, we carry out a detailed theoretical study on the potential energy surface (PES) of the CHONH2 degradation reaction to a) Provide the elaborated addition channels on the CHONH2 degradation reaction PESs; b) Give a deep insight into the mechanism of CHONH2 degradation reactions; c) Calculate the rate constant of the H-abstraction. We hope our work will provide some valuable fundamental insights into title reaction. Computational Details All Au clusters and CHONH2 molecule calculations are carried out using the Gaussian 09 program packages [30]. The geometries of all the stationaries are optimized using the hybrid density functional B3PW91 method [31]. As is known, full electron calculations for Au atom consume too much time, so it is necessary to introduce the relativistic effective core potential (RECP) to describe the inner core electrons. The 5s25p65d106s1 outermost valence electrons of the Au atom are described through the Lanl2dz base set [32, 33]. In order to obtain more reliable energetic data, higher level single-point energy calculations are performed at the multi-coefficient correlation method based on quadratic configuration interaction with single and double excitations (CCSD(T)) [34-38] by using the B3PW91 optimized geometries. To confirm that the transition states connect designated intermediates or products, intrinsic reaction coordinate (IRC) calculation is carried out at the B3PW91 level. Moreover, the CCSD(T) single-point energies with ZPE corrections are used in the following discussions. NBO method [39] is performed to study orbital interactions supported by Gaussian 09 program. The localized orbital interactions, involved in non-covalent interactions, are quantified using second order perturbation theory, in which the secondorder energy (E(2)) was used to measure the interaction strengths. We use the Arrhenius formula to calculate the rate constant. The rate constant of the rate-controlling step along the main reaction channel was calculated among the temperature range 200~2000 K, which considers the small curvature tunnel effect correction (SCT) [40,41]. Results and Discussions For our convenient discussion, the energy of reactants R is set to be zero for reference. By means of the transition states and their connected isomers or products, a schematic potential energy surface (PES) of the most relevant reaction pathways is described for the CHONH2 degradation reaction catalyzed by Aux (x=0, 1, 2, 3) cluster and the optimized structures of the important stationary points are plotted in (Figure 1). Table 1: Calculated enthalpies of formation (DH/kcal mol-1) according to eqn (1) for the adsorption CHONH2+Aux(x=0, 1, 2, 3 and 8) compounds. A CHONH2+Au0 CHONH2+Au1 CHONH2+Au2 CHONH2+Au3 CHONH2+Au8 R1 R2 R1 R2 R3 R1 R2 R1 R2 DH/kcal mol-1 0 -71.4 -63.5 -43.4 -19.6 -33.2 -33.6 Biomedical Journal of Scientific & Technical Research Volume 10Issue 5: 2018 Cite this article: Hongxia Liu, Zizhong Liu. Kinetics Study The Catalyze Mode Of The Formamide Degradation Reaction By Aux Cluster (X=0, 1, 2, 3): Point, Line Or Surface?. Biomed J Sci&Tech Res 10(5)-2018. BJSTR. MS.ID.002024. DOI: 10.26717/ BJSTR.2018.10.002024. 8154 CHONH2 Degradation Reaction by Gold Cluster The Related Energy Data on formation enthalpies constitute an excellent means to establish whether theoretically predicted phases are likely to be stable, and such data may serve as a guide to evaluate possible reaction routes. For the exploration of the thermodynamic feasibility of accessing these compounds from the elements (eq. (1)) we have also computed the total energies for CHONH2 + Aux (x=0, 1, 2, 3) in their ground state structures with full geometry optimization. The adsorption enthalpies for CHONH2 + Aux (x=0, 1, 2, 3) were calculated from the difference in the total energy which are summarized in Table 1. The results establish unambiguously that (eq. (1)) expresses endothermic process for CHONH2 + Aux (x=0, 1, 2, 3) reaction. ( ) ( ) 2 2 0, 1, 2, 3 0, 1, 2, 3 ( x x CHONH Au x R CHONH Au x + = → + = (1) The formation energy for the prototypical CHONH2 +Au1 are -71.4 and -63.5 kcal/mol respectively, indicating that CHONH2+Au1 is a thermodynamically stable phase at ambient conditions. This has already been established by a series of experimental and theoretical studies. Our estimated large positive values for the enthalpy of formation for the CHONH2+Au1 series also suggest that it might be possible to degradation compounds by singlet Au catalyst. Reaction Potential Energy Surface A schematic potential energy surface of the CHONH2 degradation reaction obtained at the CCSD(T)//B3PW91 + ZPE level is plotted in Figure 1a. On the PES for the CHONH2 degradation reaction, 1,2-hydrogen-abstraction along with the cleavage of C-N bond can give product P1 (NH3+CO) via the transition state TSRP1. While CHONH2 also can degradation reaction by other two channels with the barrier TSRP2, TSRa and TSab. In view of the four barriers, it is impossible to overcome the barrier height for these four transition states which the energy barrier is too high. According to the PES in Figure 1a, there are two one-step and one two-steps degradation reaction channels which are the possible reaction pathways. From the kinetics, the pathway form P3 is more competitive. It needs to overcome the barrier height 71.7 kcal/mol and 40.9 kcal/mol lower than TSRP1 (80.0 kcal/mol) and TSRP2 (93.7 kcal/mol) about 8.3 kcal/mol and 22.0 kcal/mol. Meanwhile, the channel of forming P1 is one-step reaction pathway which is more feasible than two-steps reaction pathway. While from the thermodynamics, the energy of product P1 (5.4 kcal