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DFT/B3LYP calculations are carried out on complexes formed by N(H)4(super + ) with aromatics to characterize the forces involved in such interactions and to gain further insight in to the nature and diversity of cation-aromatic interactions. The calculated results indicate that the protanated heterocyclic N(H)3 hydrogen-bond complexes produce the largest enthalpies.

The synthesis of a new ferrocenyl anion receptor N,N,N,N-(dimethyl, ethyl, ferrocenecarboxylic amidodimethylene) ammonium fluoborate with specially designed multiple binding sites of amide and positively charged nitrogen is described. The results for anion recognition behaviors provide insight into the combination of two interactions that enforced the anion binding ability and the binding selectivity of ferrocenyl receptor to phosphate anion.

Ab initio molecular orbital calculations are used for studying the interactions of the lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) complex with N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium (DEME), 1-ethyl-3-methylimidazolium (EMIM) cations, neutral dithylether (DEE) and the DEMETFSA complex. The attraction between the DEME cation and the LiTFSA complex has shown that the interaction between the Li cation and the oxygen atom of DEME cation has played key roles in determining the mobility of the Li cation in DEME-based room temperature ionic liquids.

Ion transport is analyzed in dilute organic liquid electrolyte solutions in which close cation-anion interactions are minimized either through steric hindrance imposed by the bulky tetrabutylammonium cation or by strong solvation of alkali metal cations by DMSO or 1-propanol. The molar conductivity has depended only on the dielectric constant and not the specific functional group in the broad family of solvents.

The diffusion of poly(diallyldimethylammonium chloride) (PDADMAC) polycations in coacervates formed from PDADMAC and the protein bovine serum albumin (BSA) is studied. Several ensembles of PDADMAC polycations with different diffusivities are observed.

The effect of 1 and 2-naphthols on the shape transition of cetyl trimethylammonium bromide (CTAB) and cetylpyridinium bromide (CPB) micelles are analyzed. Transmitting electron microscope (TEM) micrographs of vacuum-dried samples have shown spherical to rodlike micellar transition of CTAB and CPB in presence of naphthols.

The potential usefulness of the spectroscopic properties of an efficient cancer cell photosensitizer molecule is explored to understand the switching between the different prototropic forms of this molecule and know the biodistribution in membrane mimetic cationic micellar environments.

The electronic conductivity of the neat N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEME-TFSA) and DEME-TFSA-Li doped with different concentrations of lithium salt (LiTFSA) is measured and correlated with NMR measurements of the diffusion coefficients and the spin-lattice relaxation times. The lithium one-jump distance has changed with the temperature and salt concentration and has provided information on lithium transfer.

The cation transport characteristics of Prussian blue (PB) and PB + cetyltrimethylammonium bromide (CTAB) electrodes for [K.sup.+], [Na.sup.+], [Li.sup.+], and N[H.sub.4.sup.+] ions are analyzed. The symmetric redox peaks for a PB + CTAB films has represented an ideal cyclic voltammetric (CV) pattern for a PB-modified electrode.

Nitrophenoxy-tailed quaternary ammonium surfactants are synthesized and their self-assembling properties in aqueous solutions are analyzed by using various spectroscopic methods and dynamic light scattering. The shielding effect of the aromatic groups over the protons in the aliphatic chains has shown that the nitrophenoxy groups are partially inserted into the micelles and have faced many middle methylenes of the hydrophobic side chains.

The high signal-to-noise ratio (S/N) Raman spectra of [(N[H.sub.4]).sub.2]S[O.sub.4] droplets deposited on a quartz substrate which are obtained from dilute to supersaturated states upon decreasing the relative humidity (RH) are reported. The studies provide insight into interactions between ions and those between ions and water molecules in [(N[H.sub.4]).sub.2]S[O.sub.4] droplets, particularly in supersaturated states on a molecular level.

The effects of cations, anions, and water host molecules on the structural transition, tuning pattern, and ionic conductivity of double ionic clathrate hydrates occurring in confined cages as well as open channels is studied which could provide new insights into inclusion chemistry.

Experimental charge density studies are used to examine the crystal structure of the N,N,N',N'-tetramethylethylenediammonium dithiocyanate salt. Both experimental and theoretical results indicate that the inter-ion interactions even in this simplest of systems, play an integrated and complex role in the packing of the ions in the crystal.

The low-frequency dynamic characteristics of alkyl quaternary ammonium exchanged montmorillonite (SC20A) are investigated to determine the correlation between temperature-dependent changes in the interlayer structure and collective mobility of the surfactant. Overall, SC20A displayed features of alternating current universally, including time-temperature superposition, common in other types of disordered ion-conducting media.

First-principles density-functional calculations are used to investigate two competing pathways for the dissociation of water and ammonia on a Si(001) surface. Results show that the two dissociation pathways occur through the Lewis acid-base reaction between the partially positive H ion and the electron-abundant up atom of the buckled Si dimer.

A study reports the synthesis, electrical transport measurements, and conduction mechanism of a novel nanostructure, N[H.sub.4][V.sub.3][O.sub.8] single-crystalline nanobelts, which grow along the direction of [0l0]. The individual N[H.sub.4][V.sub.3][O.sub.8] nanobelt shows nonlinear, symmetric current/voltage (I/V) characteristics, with a conductivity of 0.1-1 S/cm at room temperature and a dielectric constant of ~130.

The mixed surfactant system sodium 10-undecenoate (SUD)-dodecyltrimethylammonium bromide (DTAB) was studied by computational simulation to determine the composition and structure of the mixed microstructures. The modelization predicts spherical or cylindrical micelles with a preferential composition of SUD-DTAB of about 1:2 while the system predicts a lamellar structure with a proportion of 1:1 when SUD is replaced by the saturated soap sodium undecanoate.

The second harmonic generation (SHG) intensity of surfactant tetrabutylammonium iodide (TBAI) solutions and the surface concentration are measured and evaluated as a proof of principle experiment. The variation in SHG response at intermediate bulk concentrations of sodium and potassium halide solutions that results from changes in the nonresonant water background and the high concentration solutions of sodium and potassium iodide are analyzed.

Ab initio Hartree-Fock calculations were used to derive the electronic structure and the vibrational frequencies of C[H.sub.3]([OC[H.sub.2]C[H.sub.2]).sub.n]OC[H.sub.3]-[M.sup.+]-C[F.sub.3]S[O.sub.3.sup.-](n = 2-4, M = Li, Na, and K) complexes. The varying coordination shown by the metal ion from 5-7 in such complexes is described.

The structure of N,N-dimethylethylenediammonium pentachloroantimonate(III), [[(C[H.sub.3]).sub.2]NH[(C[H.sub.2]).sub.2]N[H.sub.3]][Sb[Cl.sub.5]], NNDP, was investigated in the diamond-anvil cell. A crystallographic study of the behavior of NNDP is undertaken both to low temperature and high pressures to determine whether the structural evolution is due solely to the removal of thermal energy as temperature is decreased or whether the reduction of interatomic distances plays a dominant role.

The reaction CH3+O2 (+M)-> CH3O2 (+M) was studied in the bath gases Ar and N2 in a high temperature/high pressure flow cell at pressures ranging from 2-1000 bar and temperatures between 300 and 700K. Comparing experimental results with simplified modeling, it was concluded that despite a barrierless modeling of rate parameters (MEP) potential, there must be an unusually tight transition state characterized by a relative maximum of the anisotropy of the potential along the MEP.

Flame-sampling photoionization mass spectrometry combined with ab inito electronic structure calculations is used to identify C5[H.sub.x] (x=2-6, 8) isomers in rich flames fueled by allene, propyne, cyclopentene and benzene. The combustion chemistry of the observed C5[H.sub.x] intermediates and the impact on flame chemistry models are discussed.