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Moment representations

Having derived the symmetry relations between the expansion parameters in equation (55), we can proceed to fit the expansions through the ab initio dipole moment values. The expansion parameters in the expressions for and fiy are connected by symmetry relations since these two quantities have E symmetry in and so and fiy must be fitted together. The component ji, with A" symmetry, can be fitted separately. The variables p in equation (55) are chosen to reflect the properties of the potential surface, rather than those of the dipole moment surfaces. Therefore, the fittings of fi, fiy, fifi require more parameters than the fittings of the MB dipole moment representations. We fitted the 14,400 ab initio data points using 77 parameters for the component and 141 parameters for fi, fiy. The rms deviations attained were 0.00016 and 0.0003 D, respectively. [Pg.229]

Wright D. L., Jr., McGraw R. L., Benkovitz C. M., and Schwartz S. E. (2000) Six-moment representation of multiple aerosol populations in a sub-hemispheric chemicaltransformation model. Geophys. Res. Lett. 27, 967-970. [Pg.2055]

The Perturbing Chelate Chromophore System (B). The chelate system B may be considered effectively as three separate chelate chromophores indexed by I such that I = 1,2,3. Each individual chelate is considered to have a gound state < > and two electric dipole allowed (from the ground state ) excited states (fi, <1, so that the moment representation becomes... [Pg.77]

It is actually possible to simplify the form of the inducing power in terms of the moment representations defined earlier. Assuming an octahedral geometry of the metal-ligating atom system, and considering initially extended pi-system chelates for which the transitions are mainly long- or short-axis polarized, the inducing powers are readily shown to reduce to the form... [Pg.86]

Calculations of eight frontier molecular orbitals for D2h dimers 9 = 90°), and six frontier orbitals for D2 dimers were carried out from the four frontier orbitals of the monomers. A simplified description of the frontier orbitals evolution is reproduced in Figure 13.22, along with a transition dipole moment representation in the orthogonal and oblique bis-porphyrins. Raman resonance spectroscopy of the excited states shows that some transitions involve charge transfer between the two subunits, and that the contribution of charge transfer increases with the degree of coplanarity of the dimers. This is consistent with previous electric dipole measurements in the excited states. [Pg.628]

Equation (3.74) is a non-linear partial differential equation. Rather than try to obtain an exact analytical solution, it is far easier to be content with the information afforded by the moment representation of equation (3.72). (Some care must be used in differentiation, e.g. in using L H6pital srule.)The moment equations are ... [Pg.108]

Of the various high temperature lattice expansion formalisms advanced, Handy s was the most pertinent to wavelet analysis. As recognized in his original study, the use of a moments representation is very relevant to the space (translation) - scale, wavelet reconstruction of a function. One of the principal objectives of this work is to present this within the important class of problems corresponding to one dimensional (for simplicity), rational... [Pg.200]

One of the transition moment representations is available only from the first of these direct products, and indeed 2 n is the only allowed transition of those considered. In fact, it also tells us that the transition is only allowed if the radiation is polarized along the x or y axes of the molecule it will not occur if the radiation is polarized exclusively along the z axis. [Pg.330]

Figure Bl.2.1. Schematic representation of the dependence of the dipole moment on the vibrational coordinate for a heteronuclear diatomic molecule. It can couple with electromagnetic radiation of the same frequency as the vibration, but at other frequencies the interaction will average to zero. Figure Bl.2.1. Schematic representation of the dependence of the dipole moment on the vibrational coordinate for a heteronuclear diatomic molecule. It can couple with electromagnetic radiation of the same frequency as the vibration, but at other frequencies the interaction will average to zero.
The stochastic differential equation and the second moment of the random force are insufficient to determine which calculus is to be preferred. The two calculus correspond to different physical models [11,12]. It is beyond the scope of the present article to describe the difference in details. We only note that the Ito calculus consider r t) to be a function of the edge of the interval while the Stratonovich calculus takes an average value. Hence, in the Ito calculus using a discrete representation rf t) becomes r] tn) i]n — y n — A i) -I- j At. Developing the determinant of the Jacobian -... [Pg.267]

I is the bond length. The experimental quadrupole moment is consistent with a charge, q, of approximately 0.5e. In fact, a better representation of the electrostatic potential around the nitrogen molecule is obtained using the five-charge model shown in Figure 4.20. [Pg.205]

The rotational eigenfunctions and energy levels of a molecule for which all three principal moments of inertia are distinct (a so-called asymmetric top) can not easily be expressed in terms of the angular momentum eigenstates and the J, M, and K quantum numbers. However, given the three principal moments of inertia la, Ib, and Ic, a matrix representation of each of the three contributions to the rotational Hamiltonian... [Pg.348]

Vector representation of momenta and vector coupling approximations 7.1.2.1 Angular momenta and magnetic moments... [Pg.201]

The bending-extension coupling stiffnesses, Bjj, vary for different classes of antisymmetric laminates of generally orthotropic laminae, and, in fact, no general representation exists other than in the following force and moment resultants ... [Pg.215]

Examine the charge on the methylidene group, as well as the magnitude and direction of the molecule s dipole moment. Are they consistent with representation of the ylide as a hypervalent molecule or as a zwitterion ... [Pg.144]

The raw output of a molecular structure calculation is a list of the coefficients of the atomic orbitals in each LCAO (linear combination of atomic orbitals) molecular orbital and the energies of the orbitals. The software commonly calculates dipole moments too. Various graphical representations are used to simplify the interpretation of the coefficients. Thus, a typical graphical representation of a molecular orbital uses stylized shapes (spheres for s-orbitals, for instance) to represent the basis set and then scales their size to indicate the value of the coefficient in the LCAO. Different signs of the wavefunctions are typically represented by different colors. The total electron density at any point (the sum of the squares of the occupied wavefunctions evaluated at that point) is commonly represented by an isodensity surface, a surface of constant total electron density. [Pg.700]

The reason for file choice of this specific algdira can be justified by the correspondence between the Heisenberg and SchrOdinger representations (129). Applying this algebra to the moment expansion yields the px gators in the resolvent form,... [Pg.58]


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