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81.
Dr. Denis Leshchev Dr. Andrew J. S. Valentine Dr. Pyosang Kim Dr. Alexis W. Mills Dr. Subhangi Roy Dr. Arnab Chakraborty Dr. Elisa Biasin Prof. Kristoffer Haldrup Dr. Darren J. Hsu Dr. Matthew S. Kirschner Dr. Dolev Rimmerman Dr. Matthieu Chollet Dr. J. Michael Glownia Dr. Tim B. van Driel Prof. Felix N. Castellano Prof. Xiaosong Li Prof. Lin X. Chen 《Angewandte Chemie (International ed. in English)》2023,62(28):e202304615
Photoexcited molecular trajectories on potential energy surfaces (PESs) prior to thermalization are intimately connected to the photochemical reaction outcome. The excited-state trajectories of a diplatinum complex featuring photo-activated metal–metal σ-bond formation and associated Pt−Pt stretching motions were detected in real time using femtosecond wide-angle X-ray solution scattering. The observed motions correspond well with coherent vibrational wavepacket motions detected by femtosecond optical transient absorption. Two key coordinates for intersystem crossing have been identified, the Pt−Pt bond length and the orientation of the ligands coordinated with the platinum centers, along which the excited-state trajectories can be projected onto the calculated PESs of the excited states. This investigation has gleaned novel insight into electronic transitions occurring on the time scales of vibrational motions measured in real time, revealing ultrafast nonadiabatic or non-equilibrium processes along excited-state trajectories involving multiple excited-state PESs. 相似文献
82.
A meshless particle method based on an unconditionally stable time domain numerical scheme, oriented to electromagnetic transient simulations, is presented. The proposed scheme improves the smoothed particle electromagnetics method, already developed by the authors. The time stepping is approached by using the alternating directions implicit finite difference scheme, in a leapfrog way. The proposed formulation is used in order to efficiently overcome the stability relation constraint of explicit schemes. In fact, due to this constraint, large time steps cannot be used with small space steps and vice-versa. The same stability relation holds when the meshless formulation is applied together with an explicit finite difference scheme accounted for the time stepping. The computational tool is assessed and first simulation results are compared and discussed in order to validate the proposed approach. 相似文献
83.
Elena Barcucci Alberto Del Lungo Elisa Pergola 《Journal of Difference Equations and Applications》2013,19(4-5):435-490
In this Paper, we illustrate a method (called the ECO method) for enumerating some classes of combinatorial objects. The basic idea of this method is the following: by means of an operator that performs a "local expansion" on the objects, we give some recursive constructions of these classes. We use these constructions to deduce some new funtional equations verified by classes' generating functions. By solving the functional equations, we enumerate the combinatorial objects according to various parameters. We show some applications of the method referring to some classical combinatorial objects, such as: trees, paths, polyminoes and permutations 相似文献
84.
We consider the case of a uniform plane conductor containing a thin curve-like inhomogeneity of finite conductivity. In this article we prove that the imperfection can be uniquely determined from the boundary measurements of the first order correction term in the asymptotic expansion of the steady state voltage potential as the thickness goes to zero. 相似文献
85.
Elisa Maria Alessi Gerard GómezJosep J. Masdemont 《Communications in Nonlinear Science & Numerical Simulation》2012,17(2):854-866
We extend the analysis, started in a previous work [1], concerning the formation of lunar impact craters due to low-energy trajectories. First, we adopt the Circular Restricted Three-Body Problem and consider different choices of initial conditions inside the stable invariant manifold associated with the central invariant one in the neighborhood of the L2 equilibrium point in the Earth-Moon system. Then we move to the Bicircular Restricted Four-Body Problem to study the effect of the Sun on the distribution of impacts on the Moon’s surface. 相似文献
86.
Maria Elisa FernandesDimitri Leemans Mark Mixer 《Journal of Combinatorial Theory, Series A》2012,119(1):42-56
There is a well-known correspondence between abstract regular polytopes and string C-groups. In this paper, for each d?3, a string C-group with d generators, isomorphic to an alternating group of degree n is constructed (for some n?9), or equivalently an abstract regular d-polytope, is produced with automorphism group Alt(n). A method that extends the CPR graph of a polytope to a different CPR graph of a larger (or possibly isomorphic) polytope is used to prove that various groups are themselves string C-groups. 相似文献
87.
In this Note we deal with the finite element approximation of a transmission problem across a prefractal curve approximating the von Koch fractal curve. We construct a mesh adapted to the geometric shape of the interface and we refine it consistently with some estimates in suitable weighted Sobolev spaces. In these spaces we also obtain an approximation error estimate. To cite this article: P. Bagnerini et al., C. R. Acad. Sci. Paris, Ser. I 342 (2006). 相似文献
88.
We apply the semigroup setting of Desch and Miller to a class of stochastic integral equations of Volterra type with completely
monotone kernels with a multiplicative noise term; the corresponding equation is an infinite dimensional stochastic equation
with unbounded diffusion operator that we solve with the semigroup approach of Da Prato and Zabczyk. As a motivation of our
results, we study an optimal control problem when the control enters the system together with the noise.
相似文献
89.
Maria Elisa Fernandes Dimitri Leemans Asia Ivić Weiss 《Aequationes Mathematicae》2016,90(5):1045-1067
We study incidence geometries that are thin and residually connected. These geometries generalise abstract polytopes. In this generalised setting, guided by the ideas from the polytope theory, we introduce the concept of chirality, a property of orderly asymmetry occurring frequently in nature as a natural phenomenon. The main result in this paper is that automorphism groups of regular and chiral thin residually connected geometries need to be C-groups in the regular case and \({C^+}\)-groups in the chiral case. 相似文献
90.