Dipole systems overview

This chapter has given an overview of the structure and dynamics of lipid and water molecules in membrane systems, viewed with atomic resolution by molecular dynamics simulations of fully hydrated phospholipid bilayers. The calculations have permitted a detailed picture of the solvation of the lipid polar groups to be developed, and this picture has been used to elucidate the molecular origins of the dipole potential. The solvation structure has been discussed in terms of a somewhat arbitrary, but useful, definition of bound and bulk water molecules. 

Content. After a brief overview of molecular collisions and interactions, dipole radiation, and instrumentation (Chapter 2), we consider examples of measured collision-induced spectra, from the simplest systems (rare gas mixtures at low density) to the more complex molecular systems. Chapter 3 reviews the measurements. It is divided into three parts translational, rototranslational and rotovibrational induced spectra. Each of these considers the binary and ternary spectra, and van der Waals molecules we also take a brief look at the spectra of dense systems (liquids and solids). Once the experimental evidence is collected and understood in terms of simple models, a more theoretical approach is chosen for the discussion of induced dipole moments (Chapter 4) and the spectra (Chapters 5 and 6). Chapters 3 through 6 are the backbone of the book. Related topics, such as redistribution of radiation, electronic collision-induced absorption and emission, etc., and applications are considered in Chapter 7. 

Macrocyclization has benefitted from a variety of approaches, of which intramolecular radical l,4-addition °, Pd-catalyzed diyne cy-cloisomerization and syntheses via sulfonium ylids and ketoketenes are notable. Tandem methodologies are also in vogue, one of which illustrates the theme of transient generation of a reactive enone function. For highly condensed systems, routes via transient formation of dipoles (cf. Synth. Meth. 44, 489) are fast developing as are serial radical approaches (example s. Synth. Meth. 44, 972). However, for a general overview of current cycliza-tion techniques a recent review is worthy of note. ... 

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