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Step transitions

The traditional tool for carrying out this work is step-by-step transitions from the sets 9 to the sets from the sets e sets... [Pg.671]

The probability of a complete Brownian path is then obtained as the product of such single-time-step transition probabilities. For other types of dynamics, such as Newtonian dynamics, Monte Carlo dynamics or general Langevin dynamics, other appropriate short-time-step transition probabilities need to be used [5, 8]. [Pg.254]

For deterministic dynamics the state zt+At at time t + At is of course completely determined by the state of the system zt a time step At earlier. Therefore, the single-time-step transition probability p(zt -> zt+At) can be written in terms of a delta function... [Pg.257]

The transitions of type (c) are defined by two transition temperatures, one for decreasing (Ti/2j), and one for increasing temperature (Ti/2 ). Two-step transitions (Fig. Id), first reported in 1981 for an iron(III) complex of 2-bromo-salicylaldehyde-thiosemicarbazone [21], are relatively rare and have their origins in several sources. The most obvious is the presence of two lattice sites for the complex molecules. There are several examples of this [22]. In addition, binuclear systems can give rise to this effect, even when the environment of each metal atom is the same—in this instance the... [Pg.23]

In 1977 Driessen and van der Voort identified an extremely abrupt spin crossover with Tm of 213 K for [Fe(isoxazole)6](Cl04)2 [71]. Although various spectroscopic techniques have been employed to study this spin transition, the structural features of this compound at the time could not be determined, due to its extreme sensitivity to decomposition [71]. The same applies to the tetrafluoroborate salt that also displays a spin crossover, but in this instance a two-step transition was observed [71]. [Pg.151]

Keywords Spin crossover Dinuclear complexes Two-step transition Plateau Magnetic field Mossbauer spectroscopy... [Pg.183]

The important result of the LIESST experiments in (bt, S) is that the pho-toinduced species are not only [HS-LS] but also [HS-HS] pairs. The appearance of [HS-LS] species should be interpreted in terms of a synergy between intramolecular and intermolecular cooperative interactions which energetically stabilise the mixed pairs. However, the time dependent measurements (Fig. 14) reveal that [HS-HS] pairs are unstable and revert with time to both [HS-LS] and [LS-LS] configurations [17]. This observation is important in the comparative analysis of the two-step transition in (bt, S) (see Sect. 6). [Pg.199]

Del Villar et al. studied the phenomenon of the attenuation bands fading during the modal transition, which is not predicted by the numerical analysis presented here. They sophisticated the model first introducing a lossy overlay36 and successively the hybrid modes instead of the LP modes37. They also found in this last case a double step transition as opposed to the one step transition seen in this section. The double step transition is better observed when there is high index contrast between the cladding and the overlay and if low radial order modes are considered. [Pg.49]

Presently Monte Carlo calculations are based on the technique proposed by Metropolis [22] in 1953 which involves selecting the successive configurations in such a way that they build up a Markov chain [23], The one-step transition probabilities pij are defined as the probability that beginning from the i configuration with qj(N), the configuration j with qj,N> is reached in one step. These probabilities are the elements of the one-step probability matrix associated to the Markov chain and they must fulfill the following conditions ... [Pg.128]

If the n-steps transition probability elements are defined as the probability to reach the configuration j in n steps beginning from the configuration i and Ilj, = n (qjMarkov chain is ergodic (the ergodicity condition states that if i and j are two possible configurations with 0 and Ilj 0, for some finite n, pij(nl 0 ) and aperiodic (the chain of configurations do not form a sequence of events that repeats itself), the limits... [Pg.129]

The difficulty arises from the fact that the one-step transition probabilities of the Markov chain involve only ratios of probability densities, in which Z(N,V,T) cancels out. This way, the Metropolis Markov chain procedure intentionally avoids the calculation of the configurational integral, the Monte Carlo method not being able to directly apply equation (31). [Pg.140]

Dissociative chemisorption energies calculated by density functional theory for various molecules on a number of stepped transition metal surfaces. All values are given in eV per molecule. Positive and negative values signify endothermal and exothermal chemisorption reactions, respectively. [Pg.277]

Montroll and Shuler510 took for Wyfl a one-step transition matrix, cut off by an absorbing boundary, which amounts to setting... [Pg.180]

Film studies in the past decade have revealed the existence of another film stability mechanism If the continuous phase contains not only a small amount of surface active substances but also a "sufficient amount" of "small particles", these particles can form layers inside the draining film (see Fig. 6, right)[9,22-32]. As a result, such films thin step-wise, by several step-transitions (also called stratification) when at a step transition a layer of small particles leaves the film. [Pg.9]

Cycloadditions are useful for the preparation of cyclic ompounds. Several thermal and photoactivated cycloadditions, typically [4+2] (Diels-Alder reaction), are known. They proceed with functionalized electronically activated dienes and monenes. However, various cycloaddition reactions of alkenes and alkynes without their electronical activation, either mediated or catalysed by transition metal complexes under milder conditions, are known, offering a useful synthetic route to various cyclic compounds in one step. Transition metal complexes are regarded as templates and the reactions proceed with or without forming metallacycles [49]. [Pg.238]

The basic constructs of sequential function charts are presented in Fig. 8-61. The basic construct of a sequential function chart is the step-transition-step. But also note the constructs for OR and AND. At the divergent OR, the logic proceeds on only one of the possible paths, specifically, the one whose transition is the first to attain the true condition. At the divergent AND, the logic proceeds on all paths simultaneously, and all must complete to proceed beyond the convergent AND. This enables sequential function charts to provide parallel logic. [Pg.51]

Over the entire range of pH and temperature studied there was little or no dependence of the rate on ionic strength, that is, no salt effect. This result is consistent with the simple mechanism in that the slow step does not involve two ions. With at least one neutral molecule in the slow step, transition state theory predicts that the rate of the reactions will be independent of ionic strength. [Pg.310]

There are three general principles that accompany evolution of crystallizing PMs a) the Ostwald rule of step transitions,7 according to which systems that... [Pg.75]


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See also in sourсe #XX -- [ Pg.9 , Pg.11 , Pg.13 ]




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Cathodic transition step

Diameter step transition

Elementary surface reaction steps transition state

Frontier Orbital Interactions in the Transition States of One-Step -Cycloadditions

Frontier Orbital Interactions in the Transition States of One-Step 1,3-Dipolar Cycloadditions Sustmann Classification

Single-step reactions, transition-state

Single-step reactions, transition-state theory

The one-step transition probability matrix

Transition elementary reaction steps

Transition metal complexes reaction steps

Transition metals step

Transition state theory, rate determining steps

Transition states rate-determining step

Transitioning five-step model

Two-step transition

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