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The Ground Case

Let s start with the ground case, where all examples are ground atoms (as in Definition 6-1). The problem is stated in Section 10.3.1, and a method to solve it is explained in Section 10.3.2. Its correctness is discussed in Section 10.3.3, and it is illustrated in Section 10.3.4. [Pg.136]

The problem is correctly solved iff the natural extension of (r) is the unknown intended relation This is of course impossible to verify, so the main issue is to infer a logic algorithm that gives maximal confidence that the problem is correctly solved. [Pg.136]

decompose the graph of the compatibility relation over (1-) into its connected components. This is a classical graph theory problem, and is done by a depth-first traversal of the graph. The decomposition is unique, and the algorithm is of complexity 0(m+q), where m is E(r), and q is the number of edges of the compatibility graph. [Pg.136]

Second, partition each connected component into maximal compatible subgraphs (cliques). Non-deterministically retain, for each component, a partition that has the [Pg.136]

Finally, create a logic algorithm LA(r) from the msgs of the obtained compatible subsets (suppose there are c of them)  [Pg.137]


Task M Invoke the MSG Method (namely the ground case) on the set E for a=0 and b=, yielding LA(solve ), and invoke the MSG Method (again the ground case) on the set E for a=n=2 and b=0, yielding LA solve"). Admissibility of the provided example sets is achieved in both situations, so the use of the MSG Method is justified. The latter invocation of the MSG Method by construction always discovers a single clique, and may thus possibly miss the appropriate answer ... [Pg.176]

The methods of Tasks M and Q are non-deterministic, finite, and never fail, because of the usage of the ground case of the MSG Method. Moreover, the synthesized instances are non-deterministic and finite, for the same reason. The logic algorithm... [Pg.177]

In the case of Ru(2,2 -bipyridine)3 adsorbed on porous Vycor glass, it was inferred that structural perturbation occurs in the excited state, R, but not in the ground state [209]. [Pg.419]

Shapes of the ground- and first tln-ee excited-state wavefiinctions are shown in figure AT 1.1 for a particle in one dimension subject to the potential V = which corresponds to the case where the force acting on the... [Pg.17]

The one-dimensional cases discussed above illustrate many of die qualitative features of quantum mechanics, and their relative simplicity makes them quite easy to study. Motion in more than one dimension and (especially) that of more than one particle is considerably more complicated, but many of the general features of these systems can be understood from simple considerations. Wliile one relatively connnon feature of multidimensional problems in quantum mechanics is degeneracy, it turns out that the ground state must be non-degenerate. To prove this, simply assume the opposite to be true, i.e. [Pg.20]

Thennal dissociation is not suitable for the generation of beams of oxygen atoms, and RF [18] and microwave [19] discharges have been employed in this case. The first excited electronic state, 0( D), has a different spin multiplicity than the ground 0( P) state and is electronically metastable. The collision dynamics of this very reactive state have also been studied in crossed-beam reactions with a RF discharge source which has been... [Pg.2065]

Equations (C3.4.5) and (C3.4.6) cover the common case when all molecules are initially in their ground electronic state and able to accept excitation. The system is also assumed to be impinged upon by sources F. The latter are usually expressible as tlie product crfjo, where cr is an absorjition cross section, is tlie photon flux and ftois tlie population in tlie ground state. The common assumption is tliat Jo= q, i.e. practically all molecules are in tlie ground state because n n. This is tlie assumption of linear excitation, where tlie system exhibits a linear response to tlie excitation intensity. This assumption does not hold when tlie extent of excitation is significant, i.e. [Pg.3022]

We present state-to-state transition probabilities on the ground adiabatic state where calculations were performed by using the extended BO equation for the N = 3 case and a time-dependent wave-packet approach. We have already discussed this approach in the N = 2 case. Here, we have shown results at four energies and all of them are far below the point of Cl, that is, E = 3.0 eV. [Pg.71]

Conical intersections can be broadly classified in two topological types peaked and sloped [189]. These are sketched in Figure 6. The peaked case is the classical theoretical model from Jahn-Teller and other systems where the minima in the lower surface are either side of the intersection point. As indicated, the dynamics of a system through such an intersection would be expected to move fast from the upper to lower adiabatic surfaces, and not return. In contrast, the sloped form occurs when both states have minima that lie on the same side of the intersection. Here, after crossing from the upper to lower surfaces, recrossing is very likely before relaxation to the ground-state minimum can occur. [Pg.283]

The concept of two-state systems occupies a central role in quantum mechanics [16,26]. As discussed extensively by Feynmann et al. [16], benzene and ammonia are examples of simple two-state systems Their properties are best described by assuming that the wave function that represents them is a combination of two base states. In the cases of ammonia and benzene, the two base states are equivalent. The two base states necessarily give rise to two independent states, which we named twin states [27,28]. One of them is the ground state, the other an excited states. The twin states are the ones observed experimentally. [Pg.330]

Stabilizing resonances also occur in other systems. Some well-known ones are the allyl radical and square cyclobutadiene. It has been shown that in these cases, the ground-state wave function is constructed from the out-of-phase combination of the two components [24,30]. In Section HI, it is shown that this is also a necessary result of Pauli s principle and the permutational symmetry of the polyelectronic wave function When the number of electron pairs exchanged in a two-state system is even, the ground state is the out-of-phase combination [28]. Three electrons may be considered as two electron pairs, one of which is half-populated. When both electron pahs are fully populated, an antiaromatic system arises ("Section HI). [Pg.330]

A more general classification considers the phase of the total electronic wave function [13]. We have treated the case of cyclic polyenes in detail [28,48,49] and showed that for Hiickel systems the ground state may be considered as the combination of two Kekule structures. If the number of electron pairs in the system is odd, the ground state is the in-phase combination, and the system is aromatic. If the number of electron pairs is even (as in cyclobutadiene, pentalene, etc.), the ground state is the out-of-phase combination, and the system is antiaromatic. These ideas are in line with previous work on specific systems [40,50]. [Pg.342]

There are two mechanisms by which a phase change on the ground-state surface can take place. One, the orbital overlap mechanism, was extensively discussed by both MO [55] and VB [47] formulations, and involves the creation of a negative overlap between two adjacent atomic orbitals during the reaction (or an odd number of negative overlaps). This case was temied a phase dislocation by other workers [43,45,46]. A reaction in which this happens is... [Pg.344]


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The 2- case

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