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Fundamental measures functional , density

The simulation results for coexistence properties are from Hoover and Ree [24] and the value of L is from the work of Ohnesorge et al. [135], The result from Barker s SCF theory [94] is from the leading term (order a ) in an expansion of the mean square displacement in powers of a = (p p/p) - 1 and may be an underestimate of the true value from that theory, SCF, self-consistent field LJD, Lennard-Jones and Devonshine MWDA, modified weighted-density approximation GELA, generalized effective liquid approximation FMF, fundamental measures functional. [Pg.152]

In general, different approximations are invoked for the hard-core contribution and the attractive contribution to the free energy functional. For the hardcore contribution, two accurate approximations can be obtained from the fundamental measure theory [108] and the weighted density approximation... [Pg.119]

Lutsko, J. E. 2008. J. Chem. Phys. Density functional theory of inhomogeneous liquids. 11. A fundamental measure approach. 128 184711. [Pg.266]

Tarazona, P. Density functional for hard sphere crystals A fundamental measure approach. 2000. Phys. Rev. Lett. 84 694. [Pg.286]

Figure 16. The counterion density near a charged wall for the DFT scheme. Conditions as in Fig. 14. DFT denotes the density functional theory based on the fundamental measure theory [78], and WDA denotes the weighted density approximation based on the generalized Carnahan-Starling equation [75]. Figure 16. The counterion density near a charged wall for the DFT scheme. Conditions as in Fig. 14. DFT denotes the density functional theory based on the fundamental measure theory [78], and WDA denotes the weighted density approximation based on the generalized Carnahan-Starling equation [75].
The incident monochromatic photon-to-current conversion efficiency (IPCE), sometimes referred to also as the external quantum efficiency (EQE), is another fundamental measurement of the performance of a device. The IPCE value corresponds to the photocurrent density generated in the external circuit under monochromatic illumination of the DSSC divided by the photon flux that strikes the cell [6]. From such an experiment, the IPCE as a function of wavelength can be calculated from the following formula ... [Pg.114]

The statistical fundamentals of the definition of CV and LD are illustrated by Fig. 7.8 showing a quasi-three-dimensional representation of the relationship between measured values and analytical values which is characterized by a calibration straight line y = a + bx and their two-sided confidence limits and, in addition (in z-direction) the probability density function the measured values. [Pg.227]

One of the most powerful tools molecular simulation affords is that of measuring distribution functions and sampling probabilities. That is, we can easily measure the frequencies with which various macroscopic states of a system are visited at a given set of conditions - e.g., composition, temperature, density. We may, for example, be interested in the distribution of densities sampled by a liquid at fixed pressure or that of the end-to-end distance explored by a long polymer chain. Such investigations are concerned with fluctuations in the thermodynamic ensemble of interest, and are fundamentally connected with the underlying statistical-mechanical properties of a system. [Pg.77]

A spectrum is the distribution of physical characteristics in a system. In this sense, the Power Spectrum Density (PSD) provides information about fundamental frequencies (and their harmonics) in dynamical systems with oscillatory behavior. PSD can be used to study periodic-quasiperiodic-chaotic routes [27]. The filtered temperature measurements y t) were obtained as discrete-time functions, then PSD s were computed from Fast Fourier Transform (FFT) in order to compute the fundamental frequencies. [Pg.283]

Figure 1. Viscosity T as a function of temperature. The reduced temperature t is defined as the ratio of thermal energy k T and the heat of vaporization, which is a measure of the fluid cohesive energy density. The subscripts on r indicate the melting point and boiling point, respectively. (Used with permission from Trans Tech Publ. Ltd. W. Kurz and D. J. Fisher, Fundamentals of Solidification, 4th ed., Trans Tech Publ Ltd., Switzerland, 1998.)... Figure 1. Viscosity T as a function of temperature. The reduced temperature t is defined as the ratio of thermal energy k T and the heat of vaporization, which is a measure of the fluid cohesive energy density. The subscripts on r indicate the melting point and boiling point, respectively. (Used with permission from Trans Tech Publ. Ltd. W. Kurz and D. J. Fisher, Fundamentals of Solidification, 4th ed., Trans Tech Publ Ltd., Switzerland, 1998.)...
Lambert s law), where L is the absorption path length. The absorption coefficient a(v) is a function not only of frequency, but also of temperature, density, and, of course, the nature, composition, and state of matter (gaseous, liquid, solid) of the sample as is amply illustrated below. Absolute intensities of absorption spectra may often be determined which are of interest for the comparison of measurements with the fundamental theory and in many applications (atmospheric sciences). [Pg.56]

H2-H2-H2 rotovibrational band. Probably the most substantial measurements of the density dependence of collision-induced absorption spectra in the fundamental band near the onset of three-body effects, at densities from 15 to 400 amagat, are due to Hunt [187]. He shows a plot of y /g2 as function of the hydrogen density at six temperatures, from 40 to 300 K (Fig. 3.45). Especially at the low temperatures, these dependences are well represented by straight lines of well defined slopes, which in turn define the three-body moments. Inferred slopes are reported for both yo and y in that work. [Pg.300]

In enzymatic reactions, the transfer proceeds via phosphorylation of the OH function of the serine residue however, threonine and tyrosine can be also involved. Hence, much attention has been paid to the fundamental study of the compounds shown in Scheme 2.36 The attractiveness of these models is due to the fact that X-ray structures both for enantiomeric and racemic forms are known (with exception of O-phospho-L-tyrosine). With the local geometry of phosphate groups and hydrogen bonding pattern taken from X-ray studies, it is possible to test the correctness of NMR analysis, the accuracy of measured structural constraints and the applicability of theoretical methods (ab initio, density functional... [Pg.55]

Adsorption equilibria is important fundamental property to design and develop the adsorption process. We have measured the adsorption equilibrium constant of limonene and linalool in SC-C02 by an impulse response technique [9]. Figure 1 shows the adsorption equilibrium constant at a temperature of 313 K - 333 K and a pressure of 11.8 MPa - 23.5 MPa. Linalool was adsorbed more selectively than limonene. Adsorption equilibrium constants were correlated linearly in log-log plot as a function of the density of SC-C02 independent of pressure and temperature. Adsorbed amounts decreased with the increase in the solvent density for both limonene and linalool. These results suggest the possibility of a process where oxygenated compounds are selectively adsorbed on the adsorbent at a lower pressure and then desorbed at a higher pressure. [Pg.304]


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