Continuum quasi

S. B. Phillips and R. L. Lyke, Fluorescence kinetics of systems with a quasi-continuum of excited states, Chem. Phys. Lett. 136, 247-251 (1987). 

The separator pore structure is usually very complex. It consists of a porous network of interconnected pores, which are filled with liquid electrolyte. A complete description of the pore structure would require a very intricate model. Simulations are only practically possible if the structure is represented by a simplified quasi-continuum involving a few param-... 

In this method, the respective positions of about 100 ions (inner zone) are calculated under various assumptions for the inter-ionic potentials, assuming the rest of the lattice as a quasi-continuum. A polarization per unit cell is attributed from measured values of the static dielectric constant. The configuration within the iimer zone (which may generate a cluster ) is varied until the total energy of the lattice is minimized ... 

To discover smaller specific effects on the intramolecular dynamics after attachment of an Ar atom to the benzene molecule, we performed lifetime measurements of single rovibronic states in the 6q band of the benzene-Ar and the benzene-84 Kr complex. No dependence of the lifetime on the J K> quantum number within one vibronic band was found [38]. This is in line with the results in the bare molecule and points to a nonradiative process in the statistical limit produced by a coupling to a quasi-continuum, for example, the triplet manifold. 

Here p is the density matrix for all molecular states in the three-level system depicted in Fig. 4, and all incoherent relaxation terms caused, for example, by collisions, spontaneous emission, or decay in a (quasi)continuum are incorporated in the relaxation matrix rreiax. 

V. S. Letokhov My answer to Prof. Quack is that it is indeed difficult to predict theoretically the effect of intense femtosecond IR pulses on the IVR rate of polyatomic molecules, which is important for the transfer of vibrationally excited molecules from low-lying states to the vibrational quasi-continuum. We are developing the relevant theoretical mechanisms of IR MP E/D of polyatomics since the discovery of this effect for isotopic molecules BC13 and SF6 in 1974-1975.1 hope that it will become more realistic to study experimentally the influence of intense IR pulses on IVR due to the great progress of femtosecond laser technology. 

Results of calculations for a quasi-continuum one-dimensional model [107, 15]... 

In contrast to the quasi-continuum model, the crystal is divided into 2N cells of two types at the initial instant of time the cells with odd numbers are occupied by atoms, and the rest are empty. A vacancy can appear only in a cell with an odd number, and an interstitial atom can lie in a cell with an even number. Each cell contains not more than one defect. 

In summary, the dynamics of the electronic decay of inner-shell vacancies in a charged environment, such as created by interaction of a cluster with a high intensity FEL radiation, can be qualitatively different from the one induced by a low-intensity source. If the emitted electrons are slow enough to be trapped by the neighboring charges, the familiar exponential decay will be suppressed by quantum beats between the initial state and the quasi-continuum of discrete final states. Physically, the predicted oscillations correspond to creation of the initial vacancy due to the reflections of the emitted electron by the charged cluster potential and the subsequent inverse Auger transition. 

Others then went on to study various aspects of quasi-continuum concurrent multiscale methods. Lidirokas et al. [57] studied local stress states around Si nanopixels using this method. Bazant [58] argued that these atomistic-finite element multiscale methods cannot really capture inelastic behavior like fracture because the softening effect requires a regularization of the local region that is not resolved. 

Spectroscopic measurements (as in ARPES) based on the transfer of electrons into, or out of, the crystal, are determined by the electron s spectral function Ae. Projecting the spectral functions from the auxiliary to the physical space [2], Ae is expressed in terms of QE (Aq) and convoluted stripon-svivon (Aq Aq) terms. From the quasi-continuum of QE bands, only few, closely related to those of physical electron, contribute coherent bands, while the others contribute an incoherent background to A,. 

Sharf and Fischer14) have developed a new approach to account for the lack of a complete cancellation of intensity at the dip in the Fano line, in terms of the Fano treatment of a discrete state and a number of continua. It was shown that the Bixon-Jortner description of the quasi-continuum as a manifold of equally spaced levels with constant interactions with the discrete state and with constant transition moments from the ground state, does not comply with the quantum-... 

A similar approach has been described for the problem of two discrete states interacting with a quasi-continnum, all of which carry intensity 14>. However, in this case six quantum-mechanical rules of the type of Eq. (25) must be obeyed and the problem cannot be simply reduced to that of two discrete states and one idealized manifold, as has generally been done. Even when no oscillator strength is associated with the quasi-continuum, it is still not possible to use the two discrete states and one idealized manifold description. 

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