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The small-angle neutron scattering method is used to investigate the aqueous mixed micellar solutions of perflouropolyether carboxylic salts with ammonium counterions, as their shapes and dimensions are highly affected by the presence of the n3 surfactant. The analysis reveals that a close packing of the tails leads to a decrease in the micellar curvature and repulsions between the polar heads, which ultimately leads to a micellar growth in the ellipsoids with greater axial ratios.

Small angle neutron scattering and UV titration is used to study effect of the ratio of negative to positive charges on the structure of complexes formed by short negatively charged polyelectrolyte chains (PSS) and globular positively charged proteins (lysozyme). It is observed that the primary complexes reach a finite size, controlled by electrostatic repulsion, and then aggregate at a higher scale with a fractal dimension of 2.1 characteristic of reaction-limited colloidal aggregation.

Dissociation temperatures of gas hydrate formed in the ethane-water system are studied at pressures up to 1500 MPa. In situ neutron diffraction analysis and X-ray diffraction analysis in a diamond anvil cell showed that the gas hydrate formed in the ethane-water system at 340, 700, and 1840 MPa and room temperature belongs to the cubic structure I (CS-I).

A highly viscoelastic wormlike micellar solution of nonionic surfactants in a dilute region is reported. The results of structural investigations with small-angle neutron scattering (SANS) and the observations using dynamic light scattering (DLS) are presented.

Neutron scattering experiments are performed on fully deuterated liquid N-methylformamide at various temperatures and under pressure. The recorded data at atmospheric pressure and room temperature are analyzed to yield the molecular form factor and the distinct pair correlation function.

Quasielastic neutron scattering (QENS) spectra of water-filled MCM-41 samples are measured over the temperature range 238-298 K and the momentum transfer range 0.31-0.99 A(sup -1) to investigate the dynamics of confined water molecules. Using the Lorentzian and the stretched exponential functions, the spectra, which consist mainly of contributions from the transational diffusion of water molecules, are analyzed.

Quasielastic neutron scattering measurements have been performed, to investigate the dynamics of homologous disaccharide aqueous solutions. Neutron spectra have been collected by using the spectrometer OSIRIS at the ISIS pulsed neutron source of the Rutherford Appleton Laboratory.

The aggregation properties of single-chain cationic surfactants bearing one, two and three pyridinium headgroups are studied by using detailed small-angle neutron scattering (SANS). The critical micellar concentration (cmc) of these surfactants is estimated by measuring the specific conductance of the aqueous solution of the surfactants.

Small-angle neutron-(SANS) and X-ray-scattering (SAXS) patterns obtained at 40 degree C from 0.0729 m D2O solution of cesium dodecyl sulfate (CsDDS) is evaluated in terms of the conventional two-shell model, a three-shell model created for demonstration purposes. Findings suggest that the most reliable information on the aggregate structure is obtained when fitting the four-component model to the combined SANS + SAXS patterns.

Incorporation of the triangular mu(super 3) )[(C(CN)(sub 3)](sub -) ligand into polymeric arrays has led to a new class of spin-frustrated molecule-based magnets of the type M(super II)[(C(CN)(sub 3)](sub 2) (M = V, Cr). The crystal structure of Cr(super II)[(C(CN)(sub 3)](sub 2) (M = V, Cr) was determined from neutron powder diffraction at low temperature and was seen that it adopts an interpenetrating rutile-like topology.

The structural parameters of [Hg.sup.2} hydration were studied by neutron diffraction with isotopic substitution. It was fond that [Hg.sup.2} is hydrated by a first solvent shell of six water molecules and the Hg-O distance obtained in the neutron diffraction experiment is larger by approximately 0.1 Angstrom than that obtained by X-ray diffraction.

Neutron diffraction is used for showing cholesterol' s orientational preference in different lipid bilayers. The results have provided credibility to DMPCEs aversion for polyunsaturated fatty acids (PUFAs), which has supported the notion that domain formation is primarily driven by lipids.

The predicted structure and molecular trajectories from molecular dynamics simulation of the solvated Double-Super Helix (DSH) model of nascent high-density lipoprotein (HDL) are determined and compared with reconstituted nascent HDL. The analysis of salt bridge persistence during simulation helped in understanding the structural features of apoA1 that has formed the backbone of the lipoprotein.

High-resolution X-ray and neutron diffraction measurements, magnetometry and muon-spin rotation spectroscopy are used for probing the response of the superconducting state and crystal structure of LiFeAs to chemical substituents on both the Li and the Fe sites. The superconductivity is very sensitive to composition, where Li-deficient materials have shown a very rapid suppression of the superconducting state.

The Rietveld method from neutron diffraction data at 8-10 and 290 K was employed to determine the crystal and magnetic structures of BiMn[O.sub.3+[delta]] ([delta] = 0.03, 0.08, and 0.14). The absence of magnetic reflections in BiMn[O.sub.3.14] down to 8 K was in agreement with its spin glass magnetic state and the systematic changes of magnetic parameters in BiMn[O.sub.3+[delta]] are found to depend on [delta].

High-resolution neutron diffraction is used in conjunction with hydrogen/deuterium isotropic labeling to determine the structure of two archetypal aromatic liquids, benzene and toluene. The nature of aromatic [pi]-[pi] interactions in the liquid state is discovered by constructing a full six-dimensional spatial and orientational picture of these systems.

An inflection seen in atomic mean square displacements measured as a function of temperature on high resolution spectrometers is described by the onset of methyl group rotations. Molecular dynamics simulations have shown that the apparent transition is because of methyl group rotation entering the infinite instrumental resolution of the spectrometer.

X-ray and neutron diffraction and by [super 19]F solid state NMR spectroscopy are used for examining the structures of two cobalt hexagonal perovskites 6H-[Ba.sub.6][Co.sub.6][F.sub.0.93][O.sub.16] and 10H-[Ba.sub.5][Co.sub.5][F.sub.0.77][O.sub.12.88]. The tight binding and spin-orbit coupling as perturbation are used for showing that the difference in the spin orientations is related to the d-states of the distorted Co[O.sub.4] tetrahedral with high-spin [Co.sup.3+] ([d.sup.6]) ion.

Quasielastic neutron scattering (QENS) was used to determine the motions of phospholipids on a pico- to nanosecond time scale. The experimental results provide insight into a completely different mechanism of long-range motion on short time scales in phospholipid membranes.

NMR and several other techniques are employed to explain the properties and applications of the various iridium pincer complexes. The mechanisms and barriers involved in the interconversion taking place between the tetrahydride and dihydrogen/dihydride species are also studied.