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In this article, the structures and energies of CF3COCl in the low-lying electronic states have been determined by SA-2-CAS(8,7)/6-31G* and SA-2-MSPT2(8,7)/6-31G* calculations, which include equilibrium geometries, transition states, and three minimum-energy conical intersections (CI-1, CI-2, and CI-3) between S0 and S1 states. The AIMS method was used to carry out non-adiabatic dynamic simulations with the ab initio calculation performed at the SA-2-CAS(8,7)/6-31G* level. Upon irradiation to the S1 state, CF3COCl first relaxes to S1 minimum and then overcomes the ∼10 kcal/mol (TSS1_CCl) or ∼30 kcal/mol (TSS1_CO) barrier to the conical intersection region CI-1 or CI-3 (minor), with the S1 → S0 transition probability of 631. After non-adiabatic transition to the S0 state through CI-1, trajectories mainly distribute to three different reaction pathways, with one going back to S0 minimum through shortening of the C-Cl bond, the other forming CF3CO and Cl radicals by continuous elongation of the C-Cl distance, and another dissociating into CF3 + CO + Cl and running into the CI-3 region through elongation of C-C and C-Cl distances. Moreover, we found that the trajectories would recross to the S1 state with the recrossing probability of 13.9% through the CI-3 region due to the extremely sloped topographic character of CI-3. On the basis of time evolution of wavefunctions simulated here, the product ratio of CF3 + CO + Cl and CF3CO + Cl is 53.5%18.4%, which is consistent with the experimental value of 31. We further explain the photo-dissociation wavelength dependence of CF3COCl, and the product ratio of CF3 + CO + Cl increases with the increase in total energy.We present a theoretical model to study the origin of chiral symmetry breaking of a racemic mixture of optically active biomolecules. We consider a collection of Brownian particles, which can stay in any of the three possible isomeric states one achiral and two enantiomers. Isomers are undergoing self-regulatory reaction along with chiral inhibition and achiral decay processes. Adenine sulfate manufacturer The reaction rates of the isomeric states are guided by their neighbors as well as the thermal fluctuations of the system. We find that an alteration in the relative dominance of self-regulation, chiral inhibition, and achiral decay processes breaks the chiral symmetry of the system, which is either partial or complete. This results in four different asymmetric population states, viz., three-isomer coexistence, enantiomeric coexistence, chiral-achiral coexistence, and homochiral state. A change in the reaction condition induces nonequilibrium transition among these states. We also report that a fast stochastic self-regulation and a slow chiral inhibition and achiral decay process along with a threshold population of interacting neighbors suffice for the requisite for transition toward a completely symmetry broken state, i.e., homochirality.We study the elastic response of rigid wire frame particles in concentrated glassy suspensions to a step strain by applying the simple geometric methods developed in Paper I. The wire frame particles are comprised of thin rigid rods of length L, and their number density, ρ, is such that ρL3 ≫ 1. We specifically compare rigid rods to L-shapes made of two equal length rods joined at right angles. The behavior of wire frames is found to be strikingly different from that of rods. The linear elasticity scales like ρ3L6 for L-shaped particles, whereas it scales proportional to ρ for rods and the non-linear response shows a transition from shear hardening to shear softening at a critical density ρc∼K/kBTL6, where K is the bending modulus of the particles. For realistic particles made of double stranded DNA, this transition occurs at densities of about ρL3 ∼ 10. The reason for these differences is that wire frames can be forced to bend by the entanglements with their surroundings, whereas rods always remain straight. This is found to be very important even for small strains, with most particles being bent above a critical strain γc∼ρL3 -1.The competition of short-ranged depletion attraction and long-ranged repulsion between colloidal particles in colloid-polymer mixtures leads to the formation of heterogeneous gel-like structures. Our special focus will be on the states where the colloids arrange in thin strands that span the whole system and that we will refer to as dilute gel networks. These states occur at low packing fractions for attractions that are stronger than those at both the binodal line of the equilibrium gas-liquid phase separation and the directed percolation transition line. By using Brownian dynamics simulations, we explore the formation, structure, and aging dynamics of dilute gel networks. The essential connections in a dilute gel network are determined by constructing reduced networks. We compare the observed properties to those of clumpy gels or cluster fluids. Our results demonstrate that both the structure and the (often slow) dynamics of the stable or meta-stable heterogeneous states in colloid-polymer mixtures possess distinct features on various length and time scales and thus are richly diverse.An Au2S network model was proposed to study the structural origin, evolution, and formation mechanism of the Aun(SR)m clusters containing quasi-face-centered-cubic (fcc) cores. The Au-S framework structures of 20 quasi-fcc gold clusters had been determined from the Au2S network. Based on the Au2S network, some new quasi-fcc clusters, such as 8e- clusters Au24(SR)16, Au26(SR)18, Au26(SR)19 -, Au29(SR)21, Au30(SR)22, and Au32(SR)24, and a class of Au24+8n(SR)20+4n (n = 1, 2, 3, …) clusters were predicted. Furthermore, by studying the evolution of Au-S frameworks, it was possible to construct molecular-like reaction equations to account for the formation mechanism of quasi-fcc gold clusters, which indicated that the formation of quasi-fcc gold clusters can be understood from the stepwise 2e–reduction cluster growth pathways. The present studies showed that the Au2S network model provided a “parental” Au-S network for exploring the structural evolution of the quasi-fcc Aun(SR)m clusters. Moreover, it was possible to study the formation pathways of the Aun(SR)m clusters by studying the evolution of their Au-S frameworks.