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Spherical functions

The problem is not simplified by Eq. (15), since there exists a closed-form expression for the multi-scattering matrix for n spheres in terms of spherical Bessel and Hankel functions, spherical harmonics and 3j-symbols, where l, l and to, m are total angular momentum and z-projection quantum numbers, respectively (Henseler, Wirzba and Guhr, 1997) ... [Pg.238]

Although one may read that will have as profound an influence in organic chemistry as benzene had, for example, in the dye industry, this view is unlikely to be realized because benzene undergoes electrophilic substitution of its hydrogen atoms but C, has no easily replaceable hydrogen atoms. However, with the discovery presented above, one could prepare essentially any functionalized fiilleroid. The implication of this discovery is that specifically functionalized, spherically unsaturated molecules can be produced,... [Pg.198]

Problem 3.3 Confirm that the following Y(6,4>) functions (spherical harmonics) satisfy Eq. (3.13) ... [Pg.49]

Type of column packing Spherical particles with quaternary ammonium function Spherical particles aminated with trimethyl methyl diethyl amine amine ... [Pg.57]

A procedure similar to that which we have already reported was employed [9,10]. This involves the preparation of a pre-polymer poly(amic acid) (PAA) solution in DMAc, followed by imidization in suspension in paraffin oil. A typical procedure for the preparation of linear functionalized spherical polyimide particulates was as follows. A round-bottomed 3-necked flask was flushed with N2 and charged with a diamine in DMAc. The diamine was completely dissolved in DMAc. While solution was mechanically stirred, finely ground pyromellitic dianhydride (PMDA) was added to the mixture on an ice bath in small portions, and then stirring continued overnight at room temperature. Paraffin oil with poly(maleic anhydride-co-octadec-l-ene)(l l) (O.Swt% in oil) as a suspension stabilizer was added to the flask. The PAA solution was suspended for 2hr at 60T) at the speed of 400rpm. After that, imidization was initiated by dropwise addition of a mixture of acetic anhydride (4.0 molar excess of PMDA used) and pyridine (3.5 molar excess of PMDA used). After 24hr, the polyimide particulates were filtered, washed with dichloromethane and then dried at 80 °C in a vacuum oven. [Pg.958]

HuwQer C, Halter M, Rezwan K et al (2005) Self-assembly of functionalized spherical nanoparticles on chemically patterned microstmctures. Nanotechnology 16(12) 3045-3052... [Pg.112]

Fig. 13.5. A perturbation of the wave function is a small correction. Fig. (a) shows in a schematic way. how a wave function, spherical symmetric with respect to the nucleus, can be transformed into a function that is shifted off the nucleus. The function representing the correction is shown schematically in Fig. (b). Please note the function has symmetry of a p orbital. Fig. 13.5. A perturbation of the wave function is a small correction. Fig. (a) shows in a schematic way. how a wave function, spherical symmetric with respect to the nucleus, can be transformed into a function that is shifted off the nucleus. The function representing the correction is shown schematically in Fig. (b). Please note the function has symmetry of a p orbital.
The first, most primitive, model is the infinite barrier model (IBM). Here the electronic motion is confined by a spherical potential hole with infinitely high barriers. Once the electronic wave functions (spherical Bessel functions) and eigenvalues are known, one can proceed and calculate the dynamic polarizability a co). From this quantity the collective excitations are determined in a straightforward manner (see below). The theoretical prediction [50], shown in Figure 1.2, matches the experimental data (indicated by dots) rather well from very small to mesoscopic particle sizes. The result obtained shows that the IBM, which models the kinetic repulsion of the occupied 4d-shell of atomic Xe, works surprisingly well. This repulsion causes an enhanced electronic density, leading to the blue-shift of the surface-plasmon line. [Pg.3]

The mathematics of spherical harmonics is an accepted tool in many scientific disciplines and is treated in several classic texts. In 1939 the method was applied to orientation in materials by Hermans and Platzek, who used just P2), which is often referred to as the Hermans orientation function. Spherical harmonics were applied to liquid crystals in the theoretical work of Maier and Saupe, who again emphasized only (Pj)- However, they called it the order parameter and designated it S, setting a nomenclature which is now standard in liquid crystal studies. [Pg.123]

Qualitatively similar results are obtained for emulsions which were initiated by light or redox initiators. Despite the extreme lack of understanding and reproducibility in most cases the resulting microemulsions were monodisperse and spherical. Therefore they are principally well suited as starting material for surface-functionalized spherical particles. [Pg.298]

The Y functions are the rotational wave functions (spherical harmonic functions) and = ix r, 6, (p) is the dipole moment operator of the molecule in the Born-Oppenheimer approximation. The selection rules that result are ... [Pg.961]

The atomic case is included to illustrate how the numerical difficulties escalate as the number of nuclei increases. An atom has just one nucleus. The one-electron problem is separable and exactly soluble in the familiar spherical polar coordinates r, 9, general form R r)Y 9,spherical harmonic). This reduces equation (3) from a 3D PDE to a ID ordinary differential equation (ODE) for the function R r). This is solved numerically. Atomic HF calculations were being performed by Hartree himself and his co-workers in the 1930s, well before the advent of digital computers Further consideration of atomic HF methods is beyond the scope of this article, but a thorough discussion of one FDA implementation is available. ... [Pg.1943]

In a way, we should be surprised that there is so much symmetry in the natural world The primitive geometry of life started out as spherical, but as soon as single-celled organisms started to form colonies to specialize functions, spherical s)on-metry was replaced by radial symmetry in the case of plants, and bilateral symmetry for animals. Plants need to distinguish... [Pg.157]

The thus-obtained supported reagent was used for the benzylation of various amines and phenols. Recently, Janda et al. reported on a suspension-type ROMP of mixtures of norborn-2-ene, hydroxymethylnorborn-2-ene and a norborn-2-ene-derived crosslinker for the synthesis of hydroxyl-functionalized spherical supports [177]. After hydrogenation, the support was successfully used for... [Pg.216]

The wave function T i oo ( = 11 / = 0, w = 0) corresponds to a spherical electronic distribution around the nucleus and is an example of an s orbital. Solutions of other wave functions may be described in terms of p and d orbitals, atomic radii Half the closest distance of approach of atoms in the structure of the elements. This is easily defined for regular structures, e.g. close-packed metals, but is less easy to define in elements with irregular structures, e.g. As. The values may differ between allo-tropes (e.g. C-C 1 -54 A in diamond and 1 -42 A in planes of graphite). Atomic radii are very different from ionic and covalent radii. [Pg.45]

We first supposed that the field radiated into the piece by the transducer is known, thanks to the Champ-Sons model. Then, the main approximation used consists in making far field assumptions in the beam defect interaction area. In the case of a focused transducer we assume that the incident wavefronts on the defect are plane. This is equivalent to say that the defect is located in or near the transducer focal area and that a defect located outside this zone does not cause a significant echo. In the case of planar contact transducer, the incident wavefronts on the defect are assumed to be spherical The incident field on the defect is therefore approximated by the product of a spatial function gfp,0,z)describing the amplitude distribution in the beam and a time-delayed waveform < ) ft) representing the plane or spherical propagation in the beam. The incident field on the defect can therefore be approximated for ... [Pg.738]

Approximate solutions to Eq. 11-12 have been obtained in two forms. The first, given by Lord Rayleigh [13], is that of a series approximation. The derivation is not repeated here, but for the case of a nearly spherical meniscus, that is, r h, expansion around a deviation function led to the equation... [Pg.13]

There are many large molecules whose mteractions we have little hope of detemiining in detail. In these cases we turn to models based on simple mathematical representations of the interaction potential with empirically detemiined parameters. Even for smaller molecules where a detailed interaction potential has been obtained by an ab initio calculation or by a numerical inversion of experimental data, it is usefid to fit the calculated points to a functional fomi which then serves as a computationally inexpensive interpolation and extrapolation tool for use in fiirtlier work such as molecular simulation studies or predictive scattering computations. There are a very large number of such models in use, and only a small sample is considered here. The most frequently used simple spherical models are described in section Al.5.5.1 and some of the more common elaborate models are discussed in section A 1.5.5.2. section Al.5.5.3 and section Al.5.5.4. [Pg.204]

The scope of tire following article is to survey the physical and chemical properties of tire tliird modification of carbon, namely [60]fullerene and its higher analogues. The entluisiasm tliat was triggered by tliese spherical carbon allotropes resulted in an epidemic-like number of publications in tire early to mid-1990s. In more recent years tire field of fullerene chemistry is, however, dominated by tire organic functionalization of tire highly reactive fullerene... [Pg.2408]

To incorporate the angular dependence of a basis function into Gaussian orbitals, either spherical haimonics or integer powers of the Cartesian coordinates have to be included. We shall discuss the latter case, in which a primitive basis function takes the form... [Pg.411]

Next, we address some simple eases, begining with honronuclear diatomic molecules in E electronic states. The rotational wave functions are in this case the well-known spherical haimonics for even J values, Xr( ) symmetric under permutation of the identical nuclei for odd J values, Xr(R) is antisymmetric under the same pemrutation. A similar statement applies for any type molecule. [Pg.576]

The radial distribution Function (RDF) of an ensemble of N atoms can be interpreted as the probability distribution to find an atom in a spherical volume of... [Pg.501]

Apart from this simple result, comparison of stability predictions for the two limiting situations can be made only by direct numerical computation, and for this purpose a specific algebraic form must be assumed for the reaction rate function, and a specific shape for che catalyst pellet. In particular, Lee and Luss considered a spherical pellet and a first order... [Pg.173]

The basis sets that we have considered thus far are sufficient for most calculations. However, for some high-level calculations a basis set that effectively enables the basis set limit to be achieved is required. The even-tempered basis set is designed to achieve this each function m this basis set is the product of a spherical harmonic and a Gaussian function multiplied... [Pg.91]

I hi additional terms are spherical Gaussian functions with a width determined by the parameter L. It was found that the values of these parameters were not critical and many... [Pg.117]


See other pages where Spherical functions is mentioned: [Pg.192]    [Pg.97]    [Pg.192]    [Pg.326]    [Pg.231]    [Pg.192]    [Pg.97]    [Pg.192]    [Pg.326]    [Pg.231]    [Pg.979]    [Pg.1320]    [Pg.1370]    [Pg.2212]    [Pg.2396]    [Pg.75]    [Pg.579]    [Pg.252]    [Pg.379]    [Pg.50]    [Pg.74]    [Pg.90]    [Pg.152]    [Pg.209]    [Pg.237]    [Pg.324]    [Pg.325]   
See also in sourсe #XX -- [ Pg.7 , Pg.422 ]

See also in sourсe #XX -- [ Pg.7 , Pg.422 ]




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A Spherical Functions

Augmented spherical Neumann function

Basis spherical harmonic functions

Bessel function spherical

Central field approximation, angular momentum and spherical functions

Completeness of Vector Spherical Wave Functions

Complex spherical harmonic functions

Expansion of Ligand Set as Spherical Harmonic Functions

Function generalized spherical

Generalized spherical functions definition

Legendre functions, spherical harmonics

Modified spherical Bessel function

Normalized, spherical harmonic functions

Orthogonality generalized spherical functions

Products of Spherical Harmonic Functions

Real spherical harmonic functions

Real spherical harmonic functions product

Reflected vector spherical wave functions

Solid Spherical Harmonic Function

Spherical Bessel and Hankel functions

Spherical Gaussian basis functions

Spherical Gaussian function

Spherical Gaussian-Type Function

Spherical Neumann functions

Spherical functions Hankel

Spherical functions computational algorithm

Spherical functions normalization

Spherical functions orthogonality

Spherical functions recurrence relations

Spherical functions special values

Spherical harmonic functions

Spherical harmonic functions hydrogen atom orbitals

Spherical harmonic functions, momentum

Spherical harmonic orientation functions

Spherical polar coordinates state functions

Spherical wave functions

Spherical wave functions integral representations

Spherical wave functions radiating

Spherical wave functions regular

Spherical wave functions translation addition theorem

Spherically symmetric function

Stream function spherical coordinates

Vector spherical wave functions

Vector spherical wave functions distributed

Vector spherical wave functions harmonics

Vector spherical wave functions integral representations

Vector spherical wave functions radiating

Vector spherical wave functions regular

Vector spherical wave functions translation addition theorem

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