P-band

Fig. 10. X-band and P-band perpendicular mode EPR spectra of partially reduced T. thermophilus 7Fe Fd and Fe +-EDTA. The signsd around g = 2 in T. thermophilus Fd arises from approximately 1% of S = 1/2 [FesSJ clusters in the partially reduced sample. Taken from Ref. (,94).

The overlap between 5- and p-bands also occurs for the alkali metals and for the monovalent noble metals copper, silver, and gold, which have face-centered cubic structures. The noble metals differ from the alkalis because of the filled d-shell just below the 5-shell in energy the d-band and the 5-band overlap in the solid. 

The temperature effect on the absorption spectra is also shown in Fig. 2. One can see that the peak position and bandwidth of the P band increase with temperature, while in other bands (like the B and H bands) only its bandwidths show a positive temperature effect. It is important to note that even though the RC is a complicated system, its spectra are relatively simple and its bandwidth is not particularly broad. The above features of absorption spectra of RCs need to be taken into account when analyzing the observed absorption spectra. 

Because we are concerned only with the analysis of the absorption spectra of P band and B band, we consider the excitonic interactions among P, BL, and BM shown in Fig. 8. Here (oti, ot2,0C3,014) represent the diagonal matrix elements, while (p, (314, P23, P34) represent the off-diagonal matrix elements [67]. As shown in Introduction, a main feature of the P band is that its absorption maximum shows a pronounced temperature shift [42,52], According to the displaced oscillator model, the absorption maximum is independent of T. Although the distortion effect of potential surfaces will introduce some temperature shift, the effect cannot be as large as that shown in Fig. 2. 

From Eq. (2.38) we can see that in order to analyze the absorption spectra it is necessary to know the vibrational modes involved and their Huang-Rhys factors. Fortunately for the B band, these data have been obtained by Mathies and Boxer (see Table I) by analyzing the resonance Raman spectra [42,46,47]. But they only analyzed the B band. The data shown in Table I for the P band are from the literature [42,46,47] and from our fitting of absorption spectra [68]. 

Recently, Scherer et al. have used the 10-fs laser pulse with A,excitation = 860 nm to study the dynamical behavior of Rb. Sphaeroides R26 at room temperatures. In this case, due to the use of the 10-fs pulse both P band and B band are coherently excited. Thus the quantum beat behaviors are much more complicated. We have used the data given in Table I and Fig. 19 to simulate the quantum beat behaviors (see also Fig. 22). Without including the electronic coherence, the agreement between experiment and theory can not be accomplished. 

Before leaving this section, we should also mention that the location of the V- and jV-states, relative to the bulk band, depends on the sign of the bond energy / . If the AO s in the substrate are of s-(p-)symmetry, then P < 0(P > 0) and the V-(A/"-) states lie below the bulk s-(p-) band and are... 

From the constructions of Figs. 3.2 and 3.3, it is clear that a large electrolyte stability window Eg requires not only a large energy difference m — i, but also the absence of any cationic states above the top of the bonding anion-p band. It follows that most practical electrolytes are generally confined to fluorides, oxides and chlorides of the main-group... 

Electrons near the Fermi level are mobile and give rise to electrical conductivity. The band formed from overlap of p atomic orbitals is called the p band. The overlap of andp orbitals produces andp bands. If separation between andp atomic orbitals is large, the separation between s and p bands in metal is large. There is a bandgap in this case (Fig. 3.11). When the s-p separation is smaller, the bands overlap. 

Figure 3.11. Overlap of 5 orbitals gives rise to an 5 band, and overlap of p orbitals gives rise to a p band. The 5 and p orbitals of the atoms can be so widely spaced that there is a bandgap. In many cases the separation is less and the bands overlap.

P band heater A cell body — H exit port... 

Figures 8.7 and 8.8 show the local DOS for O and Si atoms in bulk quartz. In these calculations, the radii of O and Si were set to 1.09 and 1.0 A, respectively. The total DOS for this material was shown in Fig. 8.5. Each LDOS is split into contributions from s and p bands in the electronic structure. It can be seen that the band at the top of the valence band is dominated by p states from O atoms, with a small contribution from Si p states. The band located...

Fe—2S] clusters cysteines, 38 294 P-band spectrum, 38 191-192 X-band spectrum, 38 189 [2Fe—2S] clusters EPR spectroscopy, 38 187 excess electron localization, 38 179-180 [3Fe-4S] clusters, 38 16-24, 119-120 conversion reactions, 38 17-18 D. africanus Fd III, 38 138-144 electronic structure, 38 19 electron transfer series, 38 18-19 formation, oxidation and spin states, 38 17-22... 

A 54-year white man (5, 11" 189 lb) has a plasma total triglyceride of 105 mg/dL and total cholesterol of 431 mg/dL. Plasma HDL is 53 mg/dL. Electrophoresis of his plasma lipoproteins shows an intense p-band all others are normal. He is taking itraconazole for a persistent fungal infection. He had two older brothers who both died of myocardial infarction at 57 and 63 years of age. 

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