Water spectra model parameters

In this section we calculate the water spectrum in the range 0-1000 cm-1. This calculation is based on an analytical theory elaborated in 2005-2006 with the addition of a new criterion (38), related to the 50-cm 1 band in the low-frequency Raman spectrum. The calculation scheme was briefly described in Section II. One of our goals is to compare the spectra of liquid H20 and D20 and the relevant parameters of the model. Particularly, we consider the isotopic shift of the complex permittivity/absorption spectra and the terahertz (THz) spectra of both fluids. Additionally, in Appendix II we take into account the coupling of two modes, pertinent to elastically vibrating HB molecules. 

Furthermore, it is sometimes questionable to use literature data for modeling purposes, as small variations in process parameters, reactor hydrodynamics, and analytical equipment limitations could skew selectivity results. To obtain a full product spectrum from an FT process, a few analyses need to be added together to form a complete picture. This normally involves analysis of the tail gas, water, oil, and wax fractions, which need to be combined in the correct ratio (calculated from the drainings of the respective phases) to construct a true product spectrum. Reducing the number of analyses to completely describe the product spectrum is one obvious way to minimize small errors compounding into large variations in... 

In Fig. 2a we depict the wideband loss spectrum of water calculated in terms of the hat model for room temperature (27°C). For ice at —7°C a similar calculation (but in a much narrower band) is presented in Fig. 2b. The fitted molecular parameters are presented in Table I (some of these parameters will be determined below). During the lifetime Tor a dipole performs in water and ice about two librations and about six librations in supercooled water (mor = 5.6). 

Choosing room temperature as 20.2°C, we depict in Fig. 5a the wideband absorption frequency dependence a(v) of water H20 and in Fig. 6a we depict that of water D20. The fitted parameters of the model are presented in Table II. The total loss spectrum e"(v) is shown in Figs. 5b and 6b, respectively, for OW and HW. The solid lines in Figs. 5a,b and 6a,b mark the results of our calculations. 

Figure 12. Salt effect on the relative R 0H/R 0 quantum yield in two different solvents Water (left panel) and a 50/50% (by volume) mixture of met Hanoi/water [11c]. Circles are experimental data obtained from the relative height ratio of the two peaks in the steady-state fluorescence spectrum e.g., Figure 10. Dashed and full curves correspond to the Debye-Hiickel expression (with finite ion-size correction) [21] and the Naive Approximation [17, 11c], respectively. Both models employ the zero-salt kinetic parameters.

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