Carrier mass

The carrier concentration in the solution should be determined in replicate with sufficient precision so that the uncertainty of yield measurement does not exceed 1%. The precipitate for carrier mass determination should in all ways be identical to that obtained at the end of the procedure to avoid chemical form differences such as water content. 

The most important experimental quantity with which to recognize heavy-carrier masses is the Sommerfeld coefficient y of the electronic specific heat. In Fermi-liquid theory (Abrikosov et al. 1963, Nozieres 1964, Baym and Pethick... 

Material Mobility (cm A /s) Electrons Holes Effective carrier masses (x/We) Electrons Holes References... 

If the system contains two adsorbable components, rather than one adsorb-able component in an inert carrier, mass balance equations analogous to Eqs. (8.1) and (8.2) may be written for both species. However, since the contintiity condition must also be satisfied (C -f Cj constant) these equations are not independent and there is still only one mass transfer zone. The behavior of a system which contains an inert carrier in addition to the two adsorbable species is entirely different since two distinct mass transfer zones are then formed. The discussion of such systems is deferred uritU Chapter 9. 

Effective mass Value of carrier mass used to represent motion of a carrier in the semiconductor as though the motion were in free space. 

Double (Multiple) IDA. Since the specific activity Ov is often unknown, double IDA can be used to determine m,.. Two equal aliquots containing the same, but unknown mass m, are diluted with different known carrier masses. i ,. and m, .. After. separation of portions m2, in 2 and measurement of specific activities at, a 2 one obtains from Equation (9) ... 

The dominant role of the temperature-dependent carrier concentration implied by Fig. 5.8 permits us to draw some semi-quantitative conclusions about electronic transport in semiconducting liquid selenium. Using the simple semiconductor model, we can estimate the carrier mobility from Eq. 5.2 from the fitted prefactor in Eq. 5.1. For this purpose we assume that the carrier masses are not too different from the free electron mass, that is, nig — nif, mo- This yields an estimated carrier concentration at 400 °C, 2 3 x 10 cm. The corresponding... 

At large doping values, i.e., for the highest T<- values, the mid-IR and Drude-like responses of the high Tc cuprates eventually merge into what appears to be a single Drude-like response (Fig. 4b). Under the assumption that this response is comprised of only a single-component response, an extended Drude model is necessary to fit the data. This assumption, in turn, leads to the conclusion that the carrier mass is frequency-dependent, and that the carrier... 

Of the three parameters that determine the conductivity, the effective carrier mass, m, is most closely related to the details of the electronic band structure. For a carrier at a given point in a band structure, the effective mass is related to the curvature of ih E k) function by the equation ... 

Each term here is made up of the product of kg solvent L or kg adsorbent S, which do not change during their passage, and the concentrations X (kg solute/kg adsorbent) and Y (kg solute/kg solvent), which do. For the extrachon process of Figure 7.3b, addihonal balances are required because we do not have a convenient constant "carrier" mass available. This is taken up in lllustrahon 7.2. 

Considering its electrical and magnetic properties, ScSe like ScS and ScTe may be regarded as a monovalent metal in which the conduction electron density n corresponds to one electron per formula unit. Theoretically, n = 2.54x 10 cm" for nominal stoichiometric ScSe, Zhuze et al. [3]. The carrier density n = 1 x 10 cm" was calculated from the minimum In the diffuse reflection spectrum (at 2.26 eV) of ScSe obtained by the metal hydride method. Similarly, the effective free carrier mass m = 1.00 mo, the mobility of free carriers = 2.5 cm V" s" and the relaxation time t = 5.3x 10" s were obtained for this sample, Obolonchik et al. [5]. The reflection spectrum for a Bridgman-single crystal gives t = 2.2 x 10" s calculated with use of the Drude theory. The optical effective mass was estimated to be m = 2.9 mo [3]. 

In noncubic sohds, the phonon mode frequencies of the polar lattice vibrations depend, in general, on the phonon mode propagation direction. Likewise, directionally dependent free-chargescattering rates and the anisotropic inverse effective freefree-charge-carrier contributions. The infrared dielectric function is then represented by a complex-valued second-rank tensor s, which can be expressed in Cartesian coordinates (x,y,z) as ... 

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