Molecules in solids

Moerner W E 1996 Fligh-resolution optical spectroscopy of single molecules in solids Acc. Chem. Res. 29 563-71... 

Moerner W E, Plakhotnik T, Irngartinger T, Wild U P, Pohl D W and Hecht B 1994 Near-field optical spectroscopy of individual molecules in solids Phys. Rev. Lett. 73 2764-7... 

Skinner J L 1997 Theoretical models for the spectral dynamics of individual molecules in solids Single Molecule Optical Detection, Imaging and Spectroscopy ed T Basche, W E Moerner, M Orrit and U P Wild (Weinheim VCFI)... 

Myers A B, Tchenio P, Zgierski M Z and Moerner W E 1994 Vibronic spectroscopy of individual molecules in solids J. Chem. Phys. 98 10 377-90... 

Diffusion of ions or molecules in solids is preliminary to reaction. It takes place through the normal crystal lattices of reactants and products as well as in channels and fissures of imperfect crystals. It is slow in comparison with that in fluids even at the elevated temperatures at which such reactions have to be conducted. In cement manufacture, for instance, reaction times are 2 to 3 h at 1,200 to 1,500°C (2,192 to 2,732°F) even with 200-mesh particles. 

Lutz HD (1988) Bonding and Structure of Water Molecules in Solid Hydrates, Correlation of Spectroscopic and Structural Data. 69 125... 

Invariably, measurements of decay of reactive molecules in solid glasses are found to be nonexponential, that is, first-order plots of ln[intensity] versus time are upwardly curved, as shown in Figure 10.3. 

The unequivocal proof is furnished by the crystal inclusion behavior of simple 2-hydroxy-3-naphthalenecarboxylic acid 25a46 , and its 1-chloro derivative 25b37 since both allow the formation of a crystalline adduct ( clathratocomplex 19)) with dimethylformamide with the expected 1 1 stoichiometric ratio37. Thus, the salicylic acid function (2-hydroxycarboxylic acid group) is shown to be an excellent sensor, or a good complementary site for the dimethylformamide molecule in solid state inclusion. 

Atoms and molecules in solid state are subject to restricted motions, so that all the interactions which are orientation dependent are not averaged by molecular motion and the spectra are complex it is therefore fundamental to apply approaches able to increase the resolution... 

R. Englman, Non-Radiative Decay of Ions and Molecules in Solids, North-Holland, Amsterdam, 1979, p. 155. 

Although such reactions must take place to only a very slight extent, autoionization of thionyl chloride and selenyl chloride is presumed to produce EOCl+ and FOCI, ions. The molecules are pyramidal in the gas phase, but there is extensive bridging between molecules in solid SeOCl2. 

Some general comments on the solid-state chemistry ( From a molecular view on solids to molecules in solids ) have been reported by Simon (1995) emphasis was especially placed on the structural chemistry of metal-rich compounds formed by the metals in groups 1 to 6 and it was underlined that it is largely based on discrete and condensed clusters. In the chemistry of metals in low oxidation states, the residual valence electrons can be used for metal—metal bonding. Metal-rich compounds lie between normal valence compounds and the elemental metals themselves, with respect to their compositions, and often also with respect to their structures fragments of usual metal structures (close-packed, b.c.c., etc.) are often component units in the structures of metal-rich compounds. 

The purpose of this review is two pronged. We have discussed the far-reaching manifestations of molecular chirality in crystals on the macroscopic scale, and have described the various direct methods for the assignment of absolute configuration of chiral molecules in solids. Our analysis has been confined to the solid state, because of the difficulties associated with the direct assignment of absolute configuration in the dispersed phase (12). 

Z. A. Dreg , J. M. Lang, and H. G. Drickamer, High pressure study of flexible fluorescent dye molecules in solid polymeric media. III. p-/V,/V-dimethylaminobenzylidenemalononitrile (DMABNM)—reanalyzed. Chem. Phys., 169, 369-371 (1993). 

Isaac s theory explained the facts beautifully, but it was wrong. Even geniuses have their off days.That s important to remember because there are times when something seems to fit the facts perfectly, but you may not have all of the facts.That was the case for Isaac no one had all of the facts yet. Later experiments have shown that all molecules are always moving (even molecules in solids move by vibrating) and that they are attracted to each other.The reason the pressure increases when a gas is compressed inside a container is because the molecules crash into a different part of the container much more frequently. 

The rate of photobleaching of unisotropic dye molecules in solid polymer matrices has been investigated by Kaminov et al. I65a) bleaching rate is linearly proportional to the intensiy of the incident radiation from an argon laser, indicating a one-photon process. 

Diffusion of Reactive Molecules in Solids and Melts. New York, NY Wiley. 

That the molecules in solid and liquid water interact by hydrogen bonding and that hydrogen bonding is responsible for the anomalous properties of water compared with the other hydrides of Group 16... 

Does thermal motion make a difference for this aspect of the structure of ice Figure lb shows a snapshot from a simulation at finite temperature, prior to melting. While the perfect molecular alignments of the ideal lattice have been lost, the picture still shows discernible channels molecules in solids do move, but this motion does not affect the overall symmetry. 

Some useful generalizations can be drawn from the data given in Table 9.2. Notice, for example, that gases tend to have more entropy than liquids, which tend to have more entropy than solids. The atoms (or molecules) in solids only need enough energy to vibrate in their crystals at 298 K. More energy must be dispersed into a solid in order to break the attractions between the particles to create a liquid in which the particles are free to move about. Similarly, liquid molecules still have attractions for one another, and so additional energy must be dispersed into a liquid to break those attractions to form a gas. 

Compounds containing phosphorus can be both valuable synthetic intermediates and target compounds of solid-phase synthesis. Important synthetic intermediates include phosphonium salts and phosphorus ylides, which are key intermediates in carbonyl olefinations. Their preparation is discussed in Section 5.2.2.1. The preparation of oligonucleotides, these being the most important phosphorus-containing target molecules in solid-phase synthesis, is considered in Section 16.2. In this chapter, the preparation of phosphines, phosphonic acid derivatives, and phosphinic acid derivatives is discussed. 

VNfeuts, I., D. Kempen, A. Decode, G. Verreck, J. Peeters, M. Brewster, and G. Van den Mooter. 2005. Physical stability of the amorphous state of loperamide and two fragment molecules in solid dispersions with the polymers PVP-K30 and PVP-VA6Sur J Pharm ScE5 313-320. 

Hydrogen Bonding Effects Ab initio calculations represent a single molecule in vacuum, while experimentally molecules in solids are far from isolated. One of the early observations for phosphoric acid, H3P04, was that the Act observed experimentally ( 65 ppm) is much smaller than values obtained from simulation (Table II). Whether this is a result of a deficiency in the level of theory used, or represents intra- or inter-molecular effects on the experimental values has yet to be reconciled. 

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