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A study conducted shows that the [.sup.17.O]-enriched water vapor involves during the crystallization of molecular sieves by the dry-gel conversion methods. [.sup.17.O] NMR is a sensitive technique for monitoring the role of water in the formation of molecular sieves by dry-gel conversion methods.

A study was conducted by using FT-Raman spectroscopy in combination with thermogravimetric analysis (TGA) to investigate the adsorptive properties of n-pentane in several representative zeolite frameworks. The cations clearly interact with the n-pentane molecule, which might contribute, at least partially, to the static disorder of the guest molecule in zeolite L.

The coadsorption of p-xylene and toulene in completely siliceous zeolite ZSM-5 was examined using FT-Raman method. The results indicated that at total loadings of less than or equal to 4 molecules per unit cell (u.c.) both p-xylene and toulene molecules prefer to reside at the intersections of straight and zigzag channels.

A series of mesostructured aluminophosphate (AIPO)-based lamellar materials by several solid-state NMR techniques were characterized. The average number of Al atoms is estimated and the nature of other ancillary groups in the second coordination sphere for each P site.

The intermediate phases of molecular sieve SAPO-44, a small pore silicoaluminophosphate based molecular sieve with chabazite (CHA) structure, is studied using the FT-Raman spectroscopy. FT-Raman spectroscopy was used to gain the information regarding the evolution of the porosity in the framework and the immediate environments around the template molecules.

The conformational properties of trans-1,4-dichlorocyclohexane (DCC) adsorbed in several zeolites, including completely siliceous ZSM-5, Na-Y and siliceous Y, is examined by using FT-Raman spectroscopy. The results indicate that the conformational behavior of DCC is dependent on the zeolite framework structure, Si/Al ratio, and the charge-balancing cations.

The conformational behavior of chlorocyclohexane (CICH) adsorbed inside several representative zeolites such as completely siliceous ZSM-5, Na-Y, and siliceous Y (Si - Y) is investigated by FT-Raman spectroscopy. The results show that the conformational and dynamic properties of CICH depend on the zeolitic framework structure, the presence of charge-balancing cations, as well as the Si/Al ratio.

Several solid-state NMR techniques are used in conjunction with powder X-ray diffraction (XRD) and FT-Raman spectroscopy to characterize the structures of the intermediate phases of AlPO4-11 molecular sieve synthesis. The evolution of the gel phases as a function of crystallization time was followed by (super 31)P and (super 27)Al magic angle spinning NMR to obtain information on the local environments of Al and P atoms and by powder-XRD to detect the long range ordering of the gel samples.

Research is presented describing the use of FT-Raman spectroscopy to observe the benzene molecules located within siliceous ZSM-5.

Tricarbonyl(eta5-pentamethylcyclopentadienyl)rhenium(I) was characterized by single-crystal X-ray diffraction and high-pressure micro-Raman spectra up to 50 kbar was obtained. The pressure versus wavenumber plots showed discontinuities at about 9 kbar which pointed a possibility of a pressure-induced phase transition. The pressure dependency of the vibrational modes were analyzed on the basis of bonding interactions involved.

A study was conducted on the structure, luminescence spectroscopy, and lifetime decay dynamics of Eu2O3 nanoparticles formed in MCM-41. The results indicate that Eu2O3 nanoparticles of monoclinic structure are formed inside channels of MCM-41 by heating at 140 degrees C.

A study of the dynamic and conformational behavior of three related alkylcyclohexane molecules, cyclohexane (CH), methylcyclohexane (MCH), and trans-1,4-dimethylcyclohexane (DMCH), loaded within completely siliceous zeolite ZSM-5 by variable temperature FT-Raman spectroscopy is presented. The results show that at room temperature CH molecules inside the ZSM-5 framework undergo significant reorientational motions around different axes as well as ring inversion and that the reorientational motions cease when the temperature is lowered to 153K.