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Transition, complex probability matrix

The intramolecular hydrogen atom abstraction by a polymer peroxy radical (POO ) can take place unless six-membered (or larger) rings are formed in the transition state. It is obvious that polymer segment conformation will determine the probability of formation of a transition complex of the optimum structure. Since structural relaxation is slow in a polymer matrix and the local mobility depends on the local conformation of a segment of macromolecule, the kinetics of intramolecular reactions will be influenced by the segment conformation of the macromolecule. [Pg.32]

Although methods may be employed to reduce the cost of constructing the affinity matrix, the overall complexity of Diffusion Maps is still hampered by the eigende-composition of the forward transition probability matrix F. As such, the overall computational complexity of Diffusion Maps is 0(n ) as this is the cost of performing eigendecomposition on the n x n matrix F. [Pg.72]

In this chapter we continue our journey into the quantum mechanics of paramagnetic molecules, while increasing our focus on aspects of relevance to biological systems. For each and every system of whatever complexity and symmetry (or the lack of it) we can, in principle, write out the appropriate spin Hamiltonian and the associated (simple or compounded) spin wavefunctions. Subsequently, we can always deduce the full energy matrix, and we can numerically diagonalize this matrix to obtain the stable energy levels of the system (and therefore all the resonance conditions), and also the coefficients of the new basis set (linear combinations of the original spin wavefunctions), which in turn can be used to calculate the transition probability, and thus the EPR amplitude of all transitions. [Pg.135]

A chemical interconversion requiring an intermediate stationary Hamiltonian means that the direct passage from states of a Hamiltonian Hc(i) to quantum states related to Hc(j) has zero probability. The intermediate stationary Hamiltonian Hc(ij) has no ground electronic state. All its quantum states have a finite lifetime in presence of an electromagnetic field. These levels can be accessed from particular molecular species referred to as active precursor and successor complexes (APC and ASC). All these states are accessible since they all belong to the spectra of the total Hamiltonian, so that as soon as those quantum states in the active precursor (successor) complex that have a non zero electric transition moment matrix element with a quantum state of Hc(ij) these latter states will necessarily be populated. The rate at which they are populated is another problem (see below). [Pg.320]

As it has already been pointed out,10 the spectra of these complex molecules can be interpreted as arising from diatomic molecules. The probability, k, for the radiationless transition Si G is proportional to the square of the matrix element which mixes the two states.6,7... [Pg.335]

For multichannel scattering where there are two or more open channels, the S matrix is a true matrix with elements Sy and the cross section for the transition from channel i to channel j is proportional to 5y - Sy 2. The symmetry of collision processes with respect to the time reversal leads to the symmetric property of the S matrix, ST = S, which, in turn, leads to the principle of detailed balance between mutually reverse processes. The conservation of the flux of probability density for a real potential and a real energy requires that SSf = SfS = I, i.e., S is unitary. For a complex energy or for a complex potential, in general, the flux is not conserved and S is non-unitary. [Pg.182]

The transition probability, W (e), contains an electronic matrix element, coupling the electronic states in the semiconductor to those of the complex in solution, and the thermal distribution functions and red- The electronic matrix element is a product of the probability of tunneling through... [Pg.125]

To evaluate n2(q i) for complex values of one must integrate the classical equations of motion with complex-valued initial conditions. During the course of such a trajectory, all coordinates and momenta become complexvalued,6 1 but this causes no difficulties since the objects of physical meaning, the quantum numbers in the asymptotic regions, are real-valued for the trajectories which satisfy the appropriate double-ended boundary conditions Section IV.B of Ref. 9 discusses these points in some detail. The classical S-matrix is still given by (51), but there is now typically just one complex root of (143) for which > 0 so that the vibrational transition probability is... [Pg.119]

Figure 4 compares the UV-visible spectra in the range 400-900 nm of CR-MCM-41 as synthesised and after contact with water and ethanol solutions of CUSO4. After contact with aqueous solution (curve 2) the band due the 71-it transition at about 500 nm appears more intense and less structured and no new absorptions are seen. This can be due to a small change in the solvation state of the dye. Instead, after contact with ethanol solution (curve 3), a new absorption appears at about 630 nm and comparing curve 2 and curve 3 a sort of isosbestic point is seen at 570 nm. Absorption at 630 nm is ascribed to n-n trasition of molecules complexing Cu ions, in agreement with what observed for other metal ions complexed by CR linked to a polymeric matrix [8]. A fraction of this absorption is probably due to the weaker d-d transition of Cu ions [15]... [Pg.366]

Thus, the formation of the intermediate complex N20 ( S+) takes place through the non-adiabatic transitions between the vibronic terms (see Fig. 6-7). The probability of transition in an intersection can be calculated assuming separation of electronic and nuclear motion in the molecular system. Perturbation matrix elements can be factorized into electronic and vibrational parts the transition probability between electronic (n n ) and vibrational (pi V2) states can be presented as... [Pg.364]


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See also in sourсe #XX -- [ Pg.377 , Pg.388 ]

See also in sourсe #XX -- [ Pg.377 , Pg.388 ]




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