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Angular momentum coefficients

If we compare Eq. (4.78) with Eq. (4.73), it is clear that the algebraic three-dimensional model provides the correct rotational spectrum of a rigid linear rotor, where the (vibrational) angular momentum coefficient, ggg, is described by the algebraic parameters A 2 and A j2- The J-rotational band is obtained by recalling in Eq. (4.12), the branching law... [Pg.603]

As stated above, the CG coefficients can be worked out for any particular case using the raising and lowering operator techniques demonstrated above. Alternatively, as also stated above, the CG coefficients are tabulated (see, for example, Zare s book on angular momentum the reference to which is given earlier in this Appendix) for several values of j, j, and J. [Pg.629]

In addition to the possible multipolarities discussed in the previous sections, internal-conversion electrons can be produced by an EO transition, in which no spin is carried off by the transition. Because the y-rays must carry off at least one unit of angular momentum, or spin, there are no y-rays associated with an EO transition, and the corresponding internal-conversion coefficients are infinite. The most common EO transitions are between levels with J = = where the other multipolarities caimot contribute. However, EO transitions can also occur mixed with other multipolarities whenever... [Pg.454]

In a general contraction primitives (on a given atom) and of a given angular momentum enter all the contracted functions having that angular momentum, but with different contraction coefficients. [Pg.158]

The matrix J reduces to a Kronecker 8 in the angular momentum labels for p = j. The host wave function coefficients being known, the alloy wave function coefficients can now be calculated. The result for is [27]... [Pg.473]

The coefficients 0 are variously called angular momentum addition coefficients, or Wigner coefficients, or Clebsch-Gordan coefficients. Their importance for quantum mechanics was" first recognized by Wigner,6 who also provided a formula and a complete theory of them. The notation varies among different authors who deal with them7 ours follows most closely that of Rose. [Pg.404]

The coefficient of 1/r2 now takes the place of the operator for the square of the orbital angular momentum in the nonrelativistic Schro-dinger equation. This correspondence can be made more explicit by introducing the Johnson operator... [Pg.639]

Although long-time Debye relaxation proceeds exponentially, short-time deviations are detectable which represent inertial effects (free rotation between collisions) as well as interparticle interaction during collisions. In Debye s limit the spectra have already collapsed and their Lorentzian centre has a width proportional to the rotational diffusion coefficient. In fact this result is model-independent. Only shape analysis of the far wings can discriminate between different models of molecular reorientation and explain the high-frequency pecularities of IR and FIR spectra (like Poley absorption). In the conclusion of Chapter 2 we attract the readers attention to the solution of the inverse problem which is the extraction of the angular momentum correlation function from optical spectra of liquids. [Pg.6]

In Eq. (12), l,m are the photoelectron partial wave angular momentum and its projection in the molecular frame and v is the projection of the photon angular momentum on the molecular frame. The presence of an alternative primed set l, m, v signifies interference terms between the primed and unprimed partial waves. The parameter ct is the Coulomb phase shift (see Appendix A). The fi are dipole transition amplitudes to the final-state partial wave I, m and contain dynamical information on the photoionization process. In contrast, the Clebsch-Gordan coefficients (CGC) provide geometric constraints that are consequent upon angular momentum considerations. [Pg.276]

Equation (4.15) would be extremely onerous to evaluate by explicit treatment of the nucleons as a many-particle system. However, in Mossbauer spectroscopy, we are dealing with eigenstates of the nucleus that are characterized by the total angular momentum with quantum number 7. Fortunately, the electric quadrupole interaction can be readily expressed in terms of this momentum 7, which is called the nuclear spin other properties of the nucleus need not to be considered. This is possible because the transformational properties of the quadrupole moment, which is an irreducible 2nd rank tensor, make it possible to use Clebsch-Gordon coefficients and the Wigner-Eckart theorem to replace the awkward operators 3x,xy—(5,yr (in spatial coordinates) by angular momentum operators of the total... [Pg.78]

Ion-molecule radiative association reactions have been studied in the laboratory using an assortment of trapping and beam techniques.30,31,90 Many more radiative association rate coefficients have been deduced from studies of three-body association reactions plus estimates of the collisional and radiative stabilization rates.91 Radiative association rates have been studied theoretically via an assortment of statistical methods.31,90,96 Some theoretical approaches use the RRKM method to determine complex lifetimes others are based on microscopic reversibility between formation and destruction of the complex. The latter methods can be subdivided according to how rigorously they conserve angular momentum without such conservation the method reduces to a thermal approximation—with rigorous conservation, the term phase space is utilized. [Pg.26]

To simulate the particle-particle collision, the hard-sphere model, which is based on the conservation law for linear momentum and angular momentum, is used. Two empirical parameters, a restitution coefficient of 0.9 and a friction coefficient of 0.3, are utilized in the simulation. In this study, collisions between spherical particles are assumed to be binary and quasi-instantaneous. The equations, which follow those of molecular dynamic simulation, are used to locate the minimum flight time of particles before any collision. Compared with the soft-sphere particle-particle collision model, the hard-sphere model accounts for the rotational particle motion in the collision dynamics calculation thus, only the translational motion equation is required to describe the fluid induced particle motion. In addition, the hard-sphere model also permits larger time steps in the calculation therefore, the simulation of a sequence of collisions can be more computationally effective. The details of this approach can be found in the literature (Hoomans et al., 1996 Crowe et al., 1998). [Pg.16]

AV reciprocating tachycardia, 5 108 Axial dispersion coefficient, 10 762 Axial dispersion/mixing, 10 762-763 in adsorption columns, 2 604 in bubble tray absorbers, 2 88-89 chromatographic adsorption, 2 610 in packed column absorbers, 2 61-65 Axial dissolved oxygen profiles, 25 707-708 Axial filtration, 22 385-386 Axial-flow angular-momentum flowmeter, 22 672-673... [Pg.81]

The expansion coefficients on the right hand side of Eq. (1.25) are the Clebsch-Gordan coefficients.2 The eigenfunctions of the angular momentum, which can be written, abstractly, using Dirac notation 11, m >, satisfy the equations (h=1)... [Pg.10]

One can construct wave functions by first coupling 1 and 2 and subsequently 3 or in any other order (Figure 5.1). The angular momentum wave functions corresponding to the two coupling schemes are related by a recoupling coefficient [Eq. (B.24)],... [Pg.121]

It can also be connected with Racah polynomials [25], although it cannot be reduced to the ordinary Racah s or 6-j coefficient which performs angular momentum recoupling. Indeed, like a Racah s recoupling coefficient it is orthogonal with respect to summation on two angular momentum quantum numbers (/ and X), but contains a... [Pg.296]

In summary, proper spin eigenfunctions must be constructed from antisymmetric (i.e., determinental) wavefunctions as demonstrated above because the total S2 and total Sz remain valid symmetry operators for many-electron systems. Doing so results in the spin-adapted wavefunctions being expressed as combinations of determinants with coefficients determined via spin angular momentum techniques as demonstrated above. In... [Pg.180]


See other pages where Angular momentum coefficients is mentioned: [Pg.1031]    [Pg.2164]    [Pg.33]    [Pg.624]    [Pg.468]    [Pg.769]    [Pg.69]    [Pg.187]    [Pg.176]    [Pg.182]    [Pg.161]    [Pg.162]    [Pg.414]    [Pg.443]    [Pg.111]    [Pg.109]    [Pg.137]    [Pg.168]    [Pg.151]    [Pg.266]    [Pg.275]    [Pg.167]    [Pg.295]    [Pg.299]    [Pg.167]    [Pg.295]    [Pg.299]    [Pg.254]    [Pg.255]    [Pg.320]    [Pg.478]    [Pg.711]   


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Angular momentum

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