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Second order parameter correlation

These correlations between Stokes and anti-Stokes pulses allow for the conditional preparation of the anti-Stokes pulse with intensity fluctuations that are suppressed compared with classical light. In order to quantify the performance of this technique, we measured the second-order intensity correlation function giis MS ) and mean number of photons fi for the anti-Stokes pulse conditioned on the detection of ns photons in the Stokes channel (see Fig. 4). (For classical states of light, (f1] > 1, whereas an ideal Fock state with n photons has anti-Stokes photons grows linearly with ns, while (AS1) drops below unity, indicating the nonclassical character of the anti-Stokes photon states. In the presence of back-ground counts, gks (AN) does not increase monotonically with ns, but instead exhibits a minimum at ns = 2. The Mandel Q parameter [Mandel 1995] can be calculated using = n f((jns (AS) — 1) from these measurements we... [Pg.72]

Values for many of the parameters in Heff cannot be determined from a spectrum, regardless of the quality or quantity of the spectroscopic data, because of correlation effects. When two parameters enter into the effective Hamiltonian with identical functional forms, only their sum can be determined empirically. Sometimes it is possible to calculate, either ab initio or semiempirically, the value of one second-order parameter, thereby permitting the other correlated parameter to be evaluated from the spectrum. Often, although the parameter definition specifies a summation over an infinite number of states, the largest part or the explicitly vibration-dependent part of the parameter may be evaluated from an empirically determined electronic matrix element times a sum over calculable vibrational matrix elements and energy denominators (Wicke, et al, 1972). [Pg.241]

Here, Lo, Aq, and Vo are initial one, two and three dimensional size parameters, respectively. As a result, it is expected that they may share the common microscopic origin of the structural changes. Experimentally, it is also recognized that the refractive indices and UNB values of the films can be correlated with other parameters, such as CTE, E and s behavior. Further research is necessary to obtain a quantitative relationships between these second order parameters. [Pg.14]

MNDOC has the same functional form as MNDO, however, electron correlation is explicitly calculated by second-order perturbation theory. The derivation of the MNDOC parameters is done by fitting the correlated MNDOC results to experimental data. Electron correlation in MNDO is only included implicitly via the parameters, from fitting to experimental results. Since the training set only includes ground-state stable molecules, MNDO has problems treating systems where the importance of electron comelation is substantially different from normal molecules. MNDOC consequently performs significantly better for systems where this is not the case, such as transition structures and excited states. [Pg.87]

A more balanced description requires MCSCF based methods where the orbitals are optimized for each particular state, or optimized for a suitable average of the desired states (state averaged MCSCF). It should be noted that such excited state MCSCF solutions correspond to saddle points in the parameter space for the wave function, and second-order optimization techniques are therefore almost mandatory. In order to obtain accurate excitation energies it is normally necessarily to also include dynamical Correlation, for example by using the CASPT2 method. [Pg.147]

In this paper, the main features of the two-step method are presented and PNC calculations are discussed, both those without accounting for correlation effects (PbF and HgF) and those in which electron correlations are taken into account by a combined method of the second-order perturbation theory (PT2) and configuration interaction (Cl), or PT2/CI [100] (for BaF and YbF), by the relativistic coupled cluster (RCC) method [101, 102] (for TIF, PbO, and HI+), and by the spin-orbit direct-CI method [103, 104, 105] (for PbO). In the ab initio calculations discussed here, the best accuracy of any current method has been attained for the hyperfine constants and P,T-odd parameters regarding the molecules containing heavy atoms. [Pg.264]

However, a question arises - could similar approach be applied to chemical reactions At the first stage the general principles of the system s description in terms of the fundamental kinetic equation should be formulated, which incorporates not only macroscopic variables - particle densities, but also their fluctuational characteristics - the correlation functions. A simplified treatment of the fluctuation spectrum, done at the second stage and restricted to the joint correlation functions, leads to the closed set of non-linear integro-differential equations for the order parameter n and the set of joint functions x(r, t). To a full extent such an approach has been realized for the first time by the authors of this book starting from [28], Following an analogy with the gas-liquid systems, we would like to stress that treatment of chemical reactions do not copy that for the condensed state in statistics. The basic equations of these two theories differ considerably in their form and particular techniques used for simplified treatment of the fluctuation spectrum as a rule could not be transferred from one theory to another. [Pg.42]

Thus, introducing parameters a, / and T we can account for the essential part of the correlation effects. However, it turned out that in the framework of the semi-empirical approach, all relativistic corrections of the second order of the Breit operator improving the relative positions of the terms, are also taken into consideration (operators H2, and H s, described by formulas (1.19), (1.20) and (1.22), respectively). Indeed, as we have seen in Chapter 19, the effect of accounting for corrections Hj and H s in a general case may be taken into consideration by modifications of the integrals of electrostatic interaction, i.e. by representing them in form... [Pg.252]

Kodama et al. (1980) developed a detailed HDS and HDM model for deactivation of pellets and reactor beds. The model included reversible kinetics for coke formation, which contributed to loss of porosity. Second-order kinetics were used to describe both HDM and HDS reaction rates, and diffusivities were adjusted on the basis of contaminant volume in the pores. The model accurately traced the history of a reactor undergoing deactivation. This model, however, contains many parameters and is thus more correlative than theoretical or discriminating. [Pg.238]

Second-order rate constants for the reactions of phenacyl bromide with a number of anionic or neutral nucleophiles in 3 2 (v/v) acetone-water have been measured at several temperatures.141 Correlation analysis with the Bronsted equation or Swain-Scott equation is not satisfactory. Better results were obtained with the two-parameter Edwards equation. [Pg.321]

Similar calculations have yet to be completed for molecules with the main group X-cations for rows in the periodic table beyond the second. Nonetheless, it was found6 that the observed bond length data for the main group cations for all six rows of the periodic table correlate with s in six separate but essentially parallel trends similar to those displayed in Figure 2. In a search for a parameter that would rank all of the bond length data in a single trend, a bond order parameter p = s/r was defined where r =... [Pg.107]


See other pages where Second order parameter correlation is mentioned: [Pg.12]    [Pg.8]    [Pg.749]    [Pg.167]    [Pg.101]    [Pg.437]    [Pg.313]    [Pg.345]    [Pg.219]    [Pg.25]    [Pg.100]    [Pg.102]    [Pg.207]    [Pg.111]    [Pg.302]    [Pg.152]    [Pg.52]    [Pg.68]    [Pg.232]    [Pg.219]    [Pg.225]    [Pg.143]    [Pg.2]    [Pg.63]    [Pg.67]    [Pg.84]    [Pg.519]    [Pg.15]    [Pg.101]    [Pg.29]    [Pg.44]    [Pg.145]    [Pg.35]    [Pg.135]    [Pg.295]    [Pg.322]    [Pg.45]   
See also in sourсe #XX -- [ Pg.12 , Pg.14 ]




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