Solid-state interactions

Hence, water, ammonia, hydrogen fluoride and carbon dioxide separate from the mixture into the gaseous phase. However, despite the possibility of a solid-state interaction, the application of ammonium acetate solutions for washing of... 

Also interesting is the solid-state interaction between the water-extract-able fraction and the acetone-soluble fraction. Heating of the irradiated ferrocene at 110° C causes a sharp decrease in the water-extractable activity (from 55 to 15% in 2-3 hours). This 40% does not appear as ferrocene and is assumed to form some stable molecular species other than ferrocene. 

Fig. 38. Solid-state interactions of 37 involving Hoogsteen base-pairing of the coordinated adenine and the pendant thymine.

Another approach is that of including dynamics in the calculations. A dynamical formalism of DFT was first developed by Car and Parrinello [31], and has been employed in a wide range of areas, e.g. solvation problems, reactions on surfaces, solid-state interactions, and a variety of biochemical applications. In CP-MD one normally uses a plane wave basis to reduce the computational requirements and enable easy implementation of periodic boundary conditions. Nonetheless, CP-MD simulations are rather costly, and are normally not applied to systems larger than, say, 1-200 atoms, and over relatively short time frames. 

The solid-state interaction of enamines (428, 333a) with trans-l,2-diben-zoylethene (87) provides quantitative yields of the pyrrole derivatives 445 or 446 [140]. These remarkable 5-cascades consist of initial vinylogous Michael addition, enol/keto tautomerism, imine/enamine tautomerism, cyclization, and elimination, all within the crystal without melting. A waste-free extraordinary atom economy is achieved that cannot nearly be obtained in solution. The milling times are unusually long here (3 h) but it s certainly worth the effort... 

Anils. A large number of anils have been reported to be photo-chromic in the solid state as typified by salicylidene-2-chloroaniline shown in Figure 4 (21). Early explanations for the mechanism of photo-chromism in the anils involved aggregation and crystal lattice interactions (22-26). However, recent investigations by Cohen et al. (21,27,28) show that isolated molecules in glassy solutions also exhibit photochromic activity, thus ruling out such specific solid-state interactions as prerequisite to photochromism. 

If both enantiomers are present in a solid sample, the melting point and the solubility of the solid mixture are often found to be different than those of the pure enantiomers. This is due to the fact that the solid-state interaction of two R enantiomers or two S enantiomers is often different than the solid-state interaction of an R and an S enantiomer. (In fact, these interactions are diastereomeric.) The result is that three different scenarios are possible when a racemic mixture is crystallized from solution ... 

In the oxidation of metals, paralinear growth kinetics of oxide layers are known to be a quite usual phenomenon. Such a dependence is observed much less frequently with metallic systems due to three reasons. Firstly, the duration of investigations of the process of oxidation of metals is far longer than that in examining the solid-state interaction of two metals. Secondly, the minimal measurable thickness (or mass) of compound layers which can be detected using available techniques is in the former case much less than in the latter. Thirdly, since this anomalous dependence has no satisfactory explanation from a diffusional viewpoint, experimentalists investigating metallic systems probably prefer not to accentuate on it. 

Arena F, et al. Solid-state interactions, adsorption sites and functionality of Cu-ZnO/Zr02 catalysts in the C02 hydrogenation to CH3OH. Appl Catal A. 2008 350 16-23. 

Taraban E.A., Krivomchko O.P., Buyanov R.A. et al. Dehydration reactions and solid-state interactions in thermal treatment of mechanical mixtures of crystal hydroxides Al" with hydroxides Zn" Zhum. Neorgan. Khim. 1988 33 1824-28. 

The rule for predicting first-phase silicide formation (see 5.10.3.2.1) works for germanide formation during solid-state interactions between thin films ( 1000 A) of the transition metals Co, Hf, Mn, Ni, Pd and Rh and a thick single-crystal Ge substrate , with the exception of Pd. 

Mechanism of Vanadium Transfer. In previous literature two mechanisms of vanadium migration were postulated Uquid or gas phase vanadium transport. The results in this study lead us to propose a third alternative mechanism It appears from our data that a more appropriate mechanism involves interparticle vanadium transport which occurs as a result of a solid state interaction between vanadium containing particles. 

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