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Scaling with

Many properties in a Rydberg series scale in different ways. For example, the level spacing scales as n -1/3, which turns out to be an essential property when we come to discuss K-matrix theory in chapter 8. The same is true for core penetration, and all the properties which depend on the overlap between the core and excited electron wavefunctions (see chapters 4 and 6). The size of Rydberg states (discussed in section 2.14) scales as n 2, while transitions between adjacent levels in the Rydberg manifold, which depend on the overlap between adjacent excited states, scale as n 4. Yet more scaling rules for Rydberg series in external fields will emerge in chapter 10. [Pg.31]


Wheatley R J and Meath W J 1993 Dispersion energy damping functions, and their relative scale with interatomic separation, for (H,He,Li)-(H,He,Li) interactions Mol. Phys. 80 25... [Pg.213]

All teclmologically important properties of semiconductors are detennined by defect-associated energy levels in the gap. The conductivity of pure semiconductors varies as g expf-A CgT), where is the gap. In most semiconductors with practical applications, the size of the gap, E 1-2 eV, makes the thennal excitation of electrons across the gap a relatively unimportant process. The introduction of shallow states into the gap through doping, with either donors or acceptors, allows for large changes in conductivity (figure C2.16.1). The donor and acceptor levels are typically a few meV below the CB and a few tens of meV above the VB, respectively. The depth of these levels usually scales with the size of the gap (see below). [Pg.2882]

SCF approximation. The indices //, v, A, and o denote four atomic orbital centers, so that the number of such orbitals that needs to be calculated increases proportionally scales with ) N, where N is the number of AOs, This was an intractable task in 1965, so Pople, Santry, and Segal introduced the approximation that only integrals in which = v and J. = o (i.e., li)) would be considered and that, further-... [Pg.382]

One limitation of clique detection is that it needs to be run repeatedly with differei reference conformations and the run-time scales with the number of conformations pt molecule. The maximum likelihood method [Bamum et al. 1996] eliminates the need for reference conformation, effectively enabling every conformation of every molecule to a< as the reference. Despite this, the algorithm scales linearly with the number of conformatior per molecule, so enabling a larger number of conformations (up to a few hundred) to b handled. In addition, the method scores each of the possible pharmacophores based upo the extent to which it fits the set of input molecules and an estimate of its rarity. It is nc required that every molecule has to be able to match every feature for the pharmacophor to be considered. [Pg.673]

Within the last decade or so, these three remarkable isomers of benzene (2-4) have been synthesized (with considerable difficulty). The purpose of this computer project is to obtain the energies, enthalpies, or Gibbs free energies of compounds (1-4) and rank them according to energy on a veilical scale with the highest at the top. [Pg.326]

Microbial processes can also detoxify mercury ions and organic compounds by reducing the mercury to the elemental form, which is volatile (86). This certainly reduces the environmental impact of compounds such as methylmercury, however, such a bioprocess would have to include a mercury capture system before it could be exploited on a large scale with pubHc support. [Pg.37]

X-rays are collected and analy2ed in ema in one of two ways. In wds, x-rays are dispersed by Bragg diffraction at a crystal and refocused onto a detector sitting on a Rowland circle. This arrangement is similar to the production of monochromati2ed x-rays for xps described above. In the other approach, edx, x-rays are all collected at the same time in a detector whose output scales with the energy of the x-ray (and hence, Z of the material which produces the x-ray.) Detectors used for ema today are almost exclusively Li-drifted Si soHd-state detectors. [Pg.285]

The electronics for a balance based on EMFC technology is very similar to that shown in Figure 8 for a strain-gauge-based scale, with the exception that the weighing element consists of the EMFC cell described herein, together with the circuitry to control the current flow to the compensation cod. [Pg.328]

Scales are sensitive to force appHed in one direction only, eg, a scale with a horizontal platform is sensitive to forces appHed perpendicular to the platform. Scales should be leveled before calibration and whenever they are moved portable scales generally have a bubble level to facilitate leveling. [Pg.331]

There are two main advantages of acrylamide—acryUc-based flocculants which have allowed them to dominate the market for polymeric flocculants in many appHcation areas. The first is that these polymers can be made on a commercial scale with molecular weights up to 10—15 million which is much higher than any natural product. The second is that their electrical charge in solution and the charge density can be varied over a wide range by copolymerizing acrylamide with a variety of functional monomers or by chemical modification. [Pg.33]

Sulfur dioxide acts as a dienophile ia the Diels-Alder reaction with many dienes (253,254) and this reaction is conducted on a commercial scale with butadiene. The initial adduct, sulfolene [77-79-2] is hydrogenated to a solvent, sulfolane [126-33-0] which is useful for selective extraction of aromatic hydrocarbons from... [Pg.145]

Long-chain alcohols, such as are obtained by the hydrogenation of coconut oil, polymerization of ethylene, or the 0x0 process (qv), are sulfated on a large scale with sulfur thoxide or chlorosulfuhc acid to acid sulfates the alkaU salts are commercially important as surface-active agents (see Surfactants). Poly(vinyl alcohol) can be sulfated in pyhdine with chlorosulfuhc acid to the hydrogen sulfate (84). [Pg.200]

The kinetics of the formation of the magnesium hydroxide and calcium carbonate are functions of the concentration of the bicarbonate ions, the temperature, and the rate of release of CO2 from the solution. At temperatures up to 82°C, CaCO predominates, but as the temperature exceeds 93°C, Mg(OH)2 becomes the principal scale. Thus, ia seawater, there is a coasiderable teadeacy for surfaces to scale with an iacrease ia temperature. [Pg.241]


See other pages where Scaling with is mentioned: [Pg.408]    [Pg.57]    [Pg.95]    [Pg.115]    [Pg.406]    [Pg.846]    [Pg.910]    [Pg.1168]    [Pg.2186]    [Pg.2189]    [Pg.2365]    [Pg.212]    [Pg.80]    [Pg.80]    [Pg.245]    [Pg.276]    [Pg.367]    [Pg.239]    [Pg.455]    [Pg.558]    [Pg.503]    [Pg.1031]    [Pg.487]    [Pg.196]    [Pg.63]    [Pg.238]    [Pg.29]    [Pg.324]    [Pg.325]    [Pg.2]    [Pg.33]    [Pg.278]    [Pg.222]    [Pg.514]    [Pg.400]    [Pg.175]    [Pg.503]    [Pg.145]   
See also in sourсe #XX -- [ Pg.313 , Pg.314 , Pg.315 , Pg.316 , Pg.317 ]




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