Inclusion Chemistry with Zeolites: Nanoscale Materials by Design

Zeolites, with their crystalline microporous structures, are cordial hosts to a wide variety of guests. However, it was the abrupt and unexpected departure of one of these guests (water) from a host (stilbite) on heating which led Cronstedt, in 1756, to coin the term "zeolite" (from the Greek meaning "boiling stone") to describe this material. Since that time, approximately 40 different naturally-occurring zeolites have been discovered on earth. Recent studies of meteorite compositions have shown that these guest-host materials (e. g. , sodalite) occur in other parts of the universe as well. However, it wasn't until the twentieth century that synthetic routes to zeolites and other non-aluminosilicate molecular sieves were discovered. In addition, with the development of X-ray diffraction and the various spectroscopies, better understanding of the nature of the cavities, cages, and channels of these materials has led to the industrial exploitation of their guest-host properties. The world of zeolites has now expanded into a greater than 2 billion pound per year business, with major applications in detergent formulations, catalysis, and as adsorbents and desiccants. Their economic impact is difficult to determine; however, the improvement in gasoline yields alone (from catalytic cracking) must account for hundreds ofbillions ofdollars in increased GDP. In this volume, we have brought together a sampling of recent developments in various areas of guest-host or inclusion chemistry in zeolites.

Klappentext

Zeolites, with their crystalline microporous structure, are cordial hosts to a wide variety of guests. Traditional absorption techniques, as well as X-ray diffraction and spectroscopic techniques, have contributed to a better understanding of the nature of the host materials' characteristic cavities, cages and channels. The same techniques, coupled with powerful computational methods, have given new insights into the interactions of guest molecules with their hosts. In turn, this has led to new developments in the direction of structure during zeolite synthesis as well as potentially new applications of guest-host materials. The 11 chapters of Inclusion Chemistry with Zeolites: Nanoscale Materials by Design represent the cutting edge of modern research, describing some of the most recent studies on structure direction in synthesis, characterization techniques, computational aspects, coordination and organometallic chemistry, photochemistry, and electronic and optical materials. The diversity and wide utility of its presentation will inspire creative readers to create their own `nanoscale materials by design'.

Inhalt

1. Probing intrazeolite space.- 1. Introduction.- 2. Considerations.- 3. Characteristic absorption values for zeolite rho.- 4. Distortion of the zeolite rho lattice.- 5. Comparison of rho with other 8-ring zeolites.- 6. Characterization of ZSM-5 by sorption measurements.- 7. Quantitative aspects of adsorption measurements.- 8. Catalysis and reactions using molecular sieves as supports.- 9. Summary and conclusions.- 2. Structure-direction in zeolite synthesis.- 1. Introduction.- 2. Clathrasils.- 3. Thermochemical stability of high-silica zeolites.- 4. Kinetics of zeolite crystallization.- 5. Pure-silica large-pore materials.- 6. Heteroatoms and the structure-directing effect of organic molecules.- 7. Examples of structure-direction.- 8. Summary.- 3. Structural case studies of inclusion phenomena in zeolites: Xe in RHO and stilbene in ZSM-5.- 1. Introduction.- 2. Xenon in zeolite rho.- 3. Stilbene in ZSM-5.- 4. Zeolite-included molecules studied by NMR.- 1. Introduction.- 2. Effect of exchange in NMR spectroscopy.- 3. Xenon in zeolites.- 4. Deuterium-containing aromatics in zeolites.- 5. Summary.- 5. Absorbed molecules in microporous hosts: computational aspects.- 1. Introduction.- 2. Theoretical techniques.- 3. Examples.- 4. Conclusions.- 6. Zeolite encapsulated metal complexes.- 1. Introduction.- 2. Synthesis of zeolite encapsulated complexes.- 3. Characterization of intrazeolite complexes.- 4. Reactivity.- 5. Future trends.- 7. Coordination chemistry in zeolites.- 1. Introduction.- 2. Synthesis of complexes in zeolites.- 3. Coordination of transition metal ions with monodentate ligands.- 4. Coordination of transition metal ions with bi-or polydentate ligands.- 5. Conclusions.- 8. Zeolite guest-host interactions: implications in formation, catalysis, and photochemistry.- 1. Introduction.- 2. Entrapment as a monitor for zeolite assembly.- 3. Entrapment of organometallic complexes in zeolite Y cages.- 9. Photochemistry of organic molecules within zeolites: role of cations.- 1. Introduction.- 2. Zeolite cavities viewed as nanoscopic reaction vessels.- 3. Cationguest interaction: light-atom effect.- 4. Cationguest interaction: heavy-atom effect.- 5. Cationguest interaction: acid-base interaction.- 6. Cations as reaction cavity free volume controllers: Lebensraum effect.- 7. Role of hydrated cations.- 8. Summary.- 10. Zeolites as hosts for novel optical and electronic materials.- 1. Introduction.- 2. Metal clusters in zeolites.- 3. Semiconductors in zeolites.- 4. Conducting polymers in zeolites.- 5. Summary and prospects.- 11. Alkali-metal clusters as prototypes for electron solvation in zeolites.- 1. Introduction.- 2. Methods for the preparation of alkali-metal clusters.- 3. Spectroscopic properties of alkali-metal clusters and what they tell us about them.- 4. Prospects for the future.