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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.

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.

Neutron reflectometry is used for examining the interactions of polymer electrolyte fuel cell (PEFC) materials has comprise the triple-phase interface. The evidence of physical changes of aged Nafion films is obtained and the results have displayed a permanent increase in the thickness of the Nafion film and a decrease in the scattering length density (SLD), which are attributed to irreversible swelling of the Nafion film.

The electrochemical discharging and neutron diffraction studies are conducted to explain the size effects observed in the [Li.sub.4+x][Ti.sub.5][O.sub.12] spinel. The results demonstrate that the surface reconstruction often leads to the irreversible capacity loss at high surface lithium storage.

Small angle neutron scattering (SANS) and molecular dynamics (MD) simulations are used for characterizing the long-range structuring of aqueous solutions of isopropanol (IPA) and pyridine and the effect on structuring of guanidinium chloride (GdmCl). The studies have shown that the effects of [Gdm.sup.+] ions on protein-stabilizing interactions involving aromatic amino acid side chains have made major contributions to the denaturant activity of GdmCl, whereas interactions with the 'lumpy' aliphatic side chains are less important.

The location of cholesterol within polyunsaturated fatty acid (PUFA) bilayers doped with different amounts of monounsaturated (POPC) or disaturated (DMPC) lipids is studied by using deuterium labeling and neutron diffraction. The studies have shown that the presence of PUFA in the inner leaflet of a cellular bilayer has increased the transfer of cholesterol to the outer layer, thus modifying raft composition and the local function of a membrane.

The crystal structure of ammonia monohydrate phase II (AMH II) is determined by using a combination of ab initio computational structure prediction and structure solution from neutron powder diffraction data using direct space methods. The powder structure is complemented by an ab initio structure prediction by using density functional theory that has given an almost identical hydrogen bonding network.

Six prototype microporous metal-organic frameworks (MOFs) HKUST-1, MOF-505, MOF-508, MIL-53, MOF-5, and ZIF-8 with variable structures and porosites are examined for their acetylene storage, highlighting HKUST-1 as the highest acetylene storage material. Neutron powder diffraction studies on acetylene loaded HKUST-1 are carried out to locate the acetylene binding site within HKUST-1 and the significant contribution of open [Cu.sup.2+] sites for acetylene storage is established by their strong preferred interactions with acetylene molecules.

The neutron scattering analysis approach is employed to explain the structure of the Cu[Mn.sub.2][O.sub.4] ions with two different Jahn-Teller ions at different sites. The mechanisms associated with the occurrence of the Cu and Mn ions at different atomic positions in the oxide spinel are also discussed.

A topotactic reduction, with LiH, of the hexagonal perovskite 4H-BaMn[O.sub.3-x] was used to obtain the anion-deficient perovskite 4H-BaMn[O.sub.2-x]. The magnetization measurements and neutron diffraction data indicated that 4H-BaMn[O.sub.2+x] adopted an antiferromagnetically ordered state below TN - 350 K.

Small angle neutron and X-ray scattering is used for studying the interaction of urea with the protein ubiquitin. The pH change has triggered recruitment of urea molecules from bulk solution per ubiquitin molecule during the unfolding process.

High yields of the novel Ba[Hg.sub.2][Tl.sub.2] are achieved from reactions of the appropriate cast alloys and the tetragonal barium structure is refined from both single-crystal X-ray and neutron powder diffraction data. The thallium characteristics are close to those in numerous alkali-metal-Tl cluster systems and other active metal-mercury phases are all distinctly electron-richer and more reduced and without appreciable net 5d, 6s contributions to Hg-Hg bonding.

The characterization of the rock-salt type [Ca.sub.1-x][Mn.sub.x][O.sub.2] solid solution by the transmission electron microscopy has shown the existence of subtle extra ordering in other upper oxides of the Ca-Mn-O system. The combination of electron microscopy with powder X-ray and neutron diffraction has allowed a complete characterization of the system.

Hydrothermal synthesis, neutron diffraction and FT-IR analysis of a oxynitrate [Bi.sub.3][Mn.sub.4][O.sub.12](N[O.sub.3]) is described. The newly developed structural type included flat N[O.sub.3] layers alternating with blocks of two Pb[Sb.sub.2][O.sub.6]-like layers and showed on long-range ordering due to the competition between the nearest and the next-nearest antiferromagnetic interactions.

Inelastic neutron scattering, density functional theory, ab initio molecular dynamics, and classical molecular dynamics are used to examine the behavior of nanoconfined water in palygorskite and sepiolite. The distortions of the silicate tetrahedra observed in palygorskite and sepiolite minerals which effectively disrupt hydrogen-bonding patterns at the silicate-water interface are found to have great impact on the dynamical behavior of nanoconfined water than the actual size of the pore or the presence of coordinatively unsaturated magnesium edge sites.

The novel disilazane compound 2-pyridinetetramethyldisilazane is prepared. The competition between N-pyridine coordination and Si-H bond activation is studied through its reactivity with two ruthenium complexes.

A new form factor model is used for analyzing small-angle neutron scattering data from a thermosensitive copolymer microgel consisting of N-isopropylacrylamide (PNIPAM) and N-isopropylmethacrylamide (PNIPMAM regions). The results have shown that a one-pot synthesis has led to a highly sophisticated material with phase separated domains on a microscopic length scale.

Quasielastic incoherent neutron scattering (QENS) of [H.sub.2]O is measured in red blood cells (RBCs). The data have shown two populations of water in RBC, a major fraction of 90% that has translational properties similar to those of bulk water and a minor fraction of 10% that is interpreted as bound hydration water with significantly slower dynamics.

The homologous SrFe[O.sub.2.5] and CaFe[O.sub.2.5] is examined by temperature dependent oxygen isotope exchange as well as the inelastic neutron scattering (INS) studies. The decisive impact of lattice dynamics has given rise to structural instabilities in oxygen deficient perovskites, thus opening new concepts for the design and tailoring of low temperature oxygen ion conductors.

The magnetic properties and magnetic structures from neutron diffraction of two synthetic natrochalcites, Na[M.sup.II.sub.2]([D.sub.3][O.sub.2])[(Mo[O.sub.4]).sub.2], M= Co or Ni, are reported. The results provide insight into the temperature at which the magnetic diffraction is observed, coinciding with that of the peak in heat capacity and short-range ordering in a narrow range of temperature.

Neutron powder diffraction and inelastic neutron scattering techniques have shown that the metal-organic framework, MIL-53, has displayed a reversible structural transition between an open-pored and a closed-pored structure as a function of temperature without the presence of any guest molecules. The transition from the open to closed structure at low temperature has shown very slow kinetics.

Time-resolved X-ray and neutron scattering with theoretical calculations have shown a mechanism whereby hydrogen crystalline silicotitanate (H-CST) has achieved its remarkable ion-exchange selectivity for cesium. The studies have shown that the interactions have induced a subtle conformational rearrangement in CST that unlocks the preferred Cs site and increases the overall capacity and selectivity for ion exchange.

A new route is described for forming stable unilamellar reverse vesicles in nonpolar organic liquids, such as cyclohexane and n-hexane. The increase in the ratio of short- to long-chain lecithin has shown a spontaneous transition from reverse micelles to reverse vesicles.