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Motion chaotic

In fact, even in the solar system, despite the relative strengths of planetary attraction, there are constituents, the asteroids, with very irregular, chaotic behaviour. The issue of chaotic motion in molecules is an issue that will appear later with great salience.)... [Pg.55]

The first classical trajectory study of iinimoleciilar decomposition and intramolecular motion for realistic anhannonic molecular Hamiltonians was perfonned by Bunker [12,13], Both intrinsic RRKM and non-RRKM dynamics was observed in these studies. Since this pioneering work, there have been numerous additional studies [9,k7,30,M,M, ai d from which two distinct types of intramolecular motion, chaotic and quasiperiodic [14], have been identified. Both are depicted in figure A3,12,7. Chaotic vibrational motion is not regular as predicted by tire nonnal-mode model and, instead, there is energy transfer between the modes. If all the modes of the molecule participate in the chaotic motion and energy flow is sufficiently rapid, an initial microcanonical ensemble is maintained as the molecule dissociates and RRKM behaviour is observed [9], For non-random excitation initial apparent non-RRKM behaviour is observed, but at longer times a microcanonical ensemble of states is fonned and the probability of decomposition becomes that of RRKM theory. [Pg.1026]

Trueadsorptionisa "massaction" processratherthanamasstransferprocess.Whatthis meansisthatitwilloccurevenintheabsenceofaconcentrationgradientbetweenthebulk gas and the surface. It comes about due to the rapid and chaotic motion of the fluidphase... [Pg.250]

In contrast to dissipative dynamical systems, conservative systems preserve phase-space volumes and hence cannot display any attracting regions in phase space there can be no fixed points, no limit cycles and no strange attractors. There can nonetheless be chaotic motion in the sense that points along particular trajectories may show sensitivity to initial conditions. A familiar example of a conservative system from classical mechanics is that of a Hamiltonian system. [Pg.171]

Since V(t) = V(0) for all times t in conservative systems, Ap = 0. The presence of attractors in dissipative systems, on the other hand, implies that the available phase space volume is contracting, and thus that Ap < 0. Since chaotic motion (either in conservative or dissipative systems) yields Ai > 0, this therefore also means that, in dissipative systems, the phase space volume is both expanding along certain directions and contracting along others. [Pg.202]

The typical strategy employed in studying the behavior of nonlinear dissipative dynamical systems consists of first identifying all of the periodic solutions of the system, followed by a detailed characterization of the chaotic motion on the attractors. [Pg.209]

It is easy to see that K = 0 for regular trajectories, while completely random motion yields K = 00. Deterministic chaotic motion, on the other hand, results in K being both finite and positive. [Pg.214]

The fact that gases are readily compressible and immediately fill the space available to them suggests that molecules of gases are widely separated and in ceaseless chaotic motion. [Pg.262]

The principal axis of the cone represents the component of the dipole under the influence of the thermal agitation. The component of the dipole in the cone results from the field that oscillates in its polarization plane. In this way, in the absence of Brownian motion the dipole follows a conical orbit. In fact the direction of the cone changes continuously (because of the Brownian movement) faster than the oscillation of the electric field this leads to chaotic motion. Hence the structuring effect of electric field is always negligible, because of the value of the electric field strength, and even more so for lossy media. [Pg.11]

Theorem 1. The sufficient conditions for transition to chaotic motion in the dynamics of equality (4) is fulfilment of... [Pg.113]

In this chapter we present some results obtained by our group on scar theory in the context of molecular vibrations, and in particular for the LiNC/LiCN molecular system. This kind of (generic) systems exhibits a dynamical behavior in which regular and chaotic motions are mixed (Gutzwiller, 1990), a situation which presents significant differences with respect to the completely chaotic case considered in most references cited above, and are very important in many areas of physics and chemistry. [Pg.123]

In this paper we consider the QCD counterpart of this problem. Namely, we address the problem of regular and chaotic motion in periodically driven quarkonium. Using resonance analysis based on the Chirikov criterion of stochasticity we estimate critical values of the external field strength at which quarkonium motion enters into chaotic regime. [Pg.332]

Most examples of flow in nature and many in industry are turbulent. Turbulence is an instability phenomenon caused, in most cases, by the shearing of the fluid. Turbulent flow is characterized by rapid, chaotic fluctuations of all properties including the velocity and pressure. This chaotic motion is often described as being made up of eddies but it is important to appreciate that eddies do not have a purely circular motion. [Pg.55]

Figure 4 shows a pattern of the concentration when the chaotic motion is established as well as the evolution of the deviation from two very close initial conditions. Note that nowadays it is very difficult to prove rigorously that a strange attractor is chaotic. In accordance with [35], a nonlinear system has chaotic dynamics if ... [Pg.248]

While the conditions 1,2 can be verified approximately by simulation, proving the condition 3 is very difficult. Note that in many studies of chaotic behavior of a CSTR, only the conditions 1,2 are verified, which does not imply chaotic d3mamics, from a rigorous point of view. Nevertheless, the fulfillment of conditions 1,2, can be enough to assure the long time chaotic behavior i.e. that the chaotic motion is not transitory. From the global bifurcations and catastrophe theory other chaotic behavior can be considered throughout the disappearance of a saddle-node fixed point [10], [19], [26]. [Pg.249]

H. Aref and S.W. Jones. Chaotic motion of a solid throught ideal fluid. Phys. Fluid. A, 5(12) 3026-3028, 1993. [Pg.316]

A complex dynamical behavior was experimentally and numerically found in a system of spin- atoms in an optical resonator with near-resonant cw laser light and external static magnetic field [69]. Three-dimensional Bloch equations were solved, and a chaotic motions was found and compared with experiment. [Pg.357]

The frequency of modulation il is now the main parameter, and we are able to switch the system of SHG between different dynamics by changing the value of il. To find the regions of where a chaotic motion occurs, we calculate a Lyapunov spectrum versus the knob parameter il. The first Lyapunov exponent A,j from the spectrum is of the greatest importance its sign determines the chaos occurrence. The maximal Lyapunov exponent Xj as a function of is presented for GCL in Fig. 6a and for BCL in Fig. 6b. We see that for some frequencies il the system behaves chaotically (A-i > 0) but orderly Ck < 0) for others. The system in the second case is much more damped than in the first case and consequently much more stable. By way of example, for = 0.9 the system of SHG becomes chaotic as illustrated in Fig. 7a, showing the evolution of second-harmonic and fundamental mode intensities. The phase point of the fundamental mode draws a chaotic attractor as seen in the phase portrait (Fig. 7b). However, the phase point loses its chaotic features and settles into a symmetric limit cycle if we change the frequency to = 1.1 as shown in Fig. 8b, while Fig. 8a shows a seven-period oscillation in intensities. To avoid transient effects, the evolution is plotted for 450 < < 500. [Pg.368]

Moreover, the Poincare mappings of (3.14) at values of Pc) fixed by the existence of (5, 6) and I4 + L5 = 0 show the presence of classically chaotic motions with a bifurcation at E - 6900 cm-1 (see Fig. 6). At this bifurcation, the periodic orbit (5, 6) becomes unstable because one of its Lyapunov exponents turns positive, as shown in Fig. 7. The periodic orbit (6, 7) destabilizes by a similar scenario around E - 7200 cm-1. These results show that the interaction between the bending modes leads to classically chaotic behaviors that destabilize successively the periodic orbits. For the bulk peri-... [Pg.534]

The analysis of the classical dynamics shows a transition to chaotic motion leading to diffusion and ionization [6]. In the quantum case, interference effects lead to localization and the quantum distribution reaches a steady state that is exponentially localized (in the number of photons) around the initially excited state. As a consequence, ionization will take place only when the localization length is large enough to exceed the number of photons necessary to reach the continuum. [Pg.584]


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