Diffuse series

All members of a diffuse series consist of compound doublets, as illustrated in Figure 7.7(b), but the splitting of the >5/2 states may be too small for the close pair of... 

Following the precedent of Liveing and Dewar, Rydberg began to classify the spectra of other atoms, notably alkali atoms, into sharp, principal, and diffuse series of lines.4 Each series of lines has a common lower level and a series of ns, rcp, or nd levels, respectively, as the upper levels of the sharp, principal, and diffuse series. He realized that the wavenumbers of the series members were related and that the wavenumbers of the observed lines could be expressed as1-4... 

The fluorescence consists of a diffuse series of small granules apparently throughout the cytoplasm of infected cells. Confusion may arise from much larger, brightly staining fragments of nuclei which sometimes contaminate a culture (McGarrity et al., 1983). 

The three commonest orbitals are called s, p, and dorbitals. These letters correspond to the. sharp, principal, and diffuse series of lines identified in early chemical spectroscopy by two Cambridge chemists, James Dewar (1842-1923) and George Liveing (1827-1924). 

In the hydrogen and alkali spectra, as we have already explained for the simple Bohr theory (fig. 13, p. 112 fig. 8, p. 148), the lines which correspond to transitions from a p-term to the ground state (s-term) are called the lines of the principal scries a principal series of higher order contains the lines which lead to the next. s-teim (in our diagram to the 2,s-term). Transitions from the rZ-torrns to the jP-terms give the diffuse series, those from the 5 terms to the ji -terms... 

It had been known for over twenty-five years before Bohr s theory that the Balrner lines were not single, but appeared to be close doublets under instruments of high resolving power. There was. however, considerable disagreement as to the separation between the doublet peaks. It was particularly important to the early spectroscopists to know whether the doublet separation remained constant throughout the Balrner series, or whether it gradually decreased, since this is an important distinction in alkali spectra between the sharp and diffuse series on the one hand, and the principal series on the other. In fact, each Balrner line is a blend of sharp, principal and diffuse doublets. Complete resolution even in the most favourable case of Ha has not yet been achieved. 

Second principal series. v=2s—tnp Second diffuse series. v=2>p—md... 

In the same vein, the variation of the diffusion coeflBcient of species across the lipid membrane cannot be explained by employing hydrodynamic expressions, such as the Stokes-Einstein relation. Here one would need to consider the free-energy barrier for entrance into the layer for each species, charged (positive or negative) and neutral the free-energy barrier is expected to be different even for same-sized species. The lipid bilayer diffusion series (LBDS) given by Eq. (12.2) is a manifestation of such microscopic effects. 

A series of tris-phenanthroline complexes of Fe(III) was used to test the relationship between the free energy AG, and the activation energy AG, in redox reactions. Different substituents in the 5 and 6 positions of the 1,lO-phenanthroline cause different redox potentials of its Fe(III)-complexes, without a marked change in their size and charge. It is therefore reasonable to assume that the configuration in the transition state of these Fe(III)complexes, with the same electron donor complex, is similar, so that only the change in the free energy of these ET reactions should influence the activation barrier. In Table 1 the measured ET rate constants k a d their values corrected for diffusion series... 

Figure 2.2 Schematic emission spectra of H, K, and Hg atoms. These are plotted versus the line frequencies v = 1/A in units of cm V where the A are the emission wavelengths in vacuum. Only the strongest emission lines are included, and relative line intensities are not shown. Line headers for H and K denote series of lines resulting from transitions terminating at a common lower level. Line headers are omitted for the Pfund series in H (which appears at extreme left) and for the sharp series in K, which closely overlaps the diffuse series.

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