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The orientation of the cation and the anion of 1-butyl-3-methylimidazolium dicyanamide at the platinum-liquid interface are reported, using sum frequency generation (SFG) spectroscopy. Results suggest that the imidazolium ring in the cation tends to lie flat at the surface of the electrode at negative potentials but is repelled at positive ones, while the anion is strongly adsorbed at the surface of the platinum at more positive potentials with its [C.sub.2] axis aligned with the surface normal.

Sum frequency generation spectroscopy is used to study the influence of water on the surface of the water-miscible ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4]. The results suggest that water has no drastic effect on the surface orientation of [BMIM][BF4] cation for concentrations from 0.0002[X.sub.IL] to 1[X.sub.IL].

In situ sum frequency generation vibrational spectroscopy was performed at varied potentials and polarization combinations on polycrystalline copper, platinum and gold samples in 0.5M HCl[O.sub.4] with 50mM 5-methylbenzotriazole 5-methylBTAH added. For copper surfaces orientation of the molecule on the surface was not affected by potential within the potential window studied and sum frequency generation spectra of 5-methyBTAH on platinum show a change in orientation over the potential range studied.

Sum frequency generation vibrational spectroscopy was used to characterize the interfacial properties of two ionic liquids as well as 1-methylimidazole and 1-butylimidazole on a quartz surface and Raman spectroscopy was used to identify vibrations and conclude whether they were symmetric or asymmetric. It was concluded that larger the anion the more the imidazolium ring was tilted towards normal.

Sum frequency generation spectroscopy (SFG) is used for the surface characterization at the gas-liquid interface of the 1-butyl-3-methylimidazolium cation combined with Br(super -), I(super -), PF(sub 6)(super -), BF(sub 4)(super -), (CF(sub 3)SO(sub 2))(sub 2)N(super -), SCN(super -), CH(sub 3)SO(sub 3)(super -), SH(sub 3)SO(sub 4)(super -), and [CN(sub 2)]N(super -) (DCN) anions. The analysis of the polarization-dependent SFG spectra has provided a reliable characterization of the cation at the liquid-gas interface.

The sum frequency generation imaging microscopy (SFGIM) is used to image the chemically distinct regions of a microcontact-printed monolayer surface. The SFGIM technique is able to obtain a vibrational spectrum at each point on the surface and demonstrate that the stamped area has a significant mixing with the molecules deposited from the backfilling solution.

The study investigates the surface of aqueous acetic acid solution using the vibrational sum frequency spectroscopy. It concluded that the orientation of the interfacial acetic acid molecules was found to remain essentially constant in an upright position with the methyl group directed toward the gas phase in the whole concentration range.

The study of aqueous acetic acid solutions is presented by vibrational sum frequency spectroscopy (VSFS) in order to acquire molecular information about the liquid-gas interface. It concluded that even such a small amounts as 0.3% acetic acid disrupt the water surface significantly.

The synthesis of two new taxoid derivatives containing the baccatin [14,1-d] dehydrofuran-2-one and -furan-2-one nucleus respectively is described. Esterification of 13-enol derivative and 13-hydroxy compound with N, O-protected norstatine followed by deprotection gave new promising anticancer taxanes.

Sum frequency generation vibrational spectroscopy (SFG) and cyclic voltammetry (CV) measurements are conducted on the ionic liquid/platinum electrode system. The SFG spectra indicate that the cation changes orientation as the electrode potential is changed within the double-layer region.

A report on an investigation on the aggregation of 1,2-dilauroyl-sn-glycero-3-phosphatidyluridine (DLPU), a surfactant molecule that merges the self-assembling properties of lecithins with the molecular recognition characteristics of nucleic bases in a phosphate-buffered aqueous solution at physiological pH and as a functin of lipid concentration is presented.

For developing a molecular-level mechanism of the heterogeneous interactions at the aqueous interface the important factor is in determining the changes in the interface with changes in the bulk composition. To probe these changes development of the nonlinear spectroscopy, sum frequency generation (SFG) provides a technique.

Solvent molecules at the Pt(111) electrode in a water/acetonitrile mixture were studied using sum frequency generation.

Sum-frequency generation vibrational spectroscopy was used to detect segregation of end groups on polymers.

Issues concerning the use of sum frequency generation to examine the vapor-liquid interface of aqueous inorganic salt and acid solutions are presented.

Results obtained using sum frequency generation show that carbon monoxide adsorbed on the platinum surface occupies both 3-fold and top-site positions on Pt(111) and only top site on polycrystalline platinum electrodes.

Research was conducted to examine the surfaces of aqueous HNO3 solutions and liquid HNO3 via sum frequency generation (SFG). An increased alignment of hydrogen-bonded water with the surface normal was indicated by the enhanced SFG intensity in the 3000-3600 cm-1 region of 0.005x and 0.01 HNO3 solutions. A electric double layer consisting of subsurface cations and anions was observed which was in agreement with the SFG spectra.

A spectroscopic study was conducted to investigate the vibrational structure of water molecules at the surface of aqueous ionic solutions using sum frequency generation. Results of the study show that the orientation of surface water molecules is influenced by the composition of the bulk solution. Dissolved, non surface-active ions re-orient water at the interface. Experimental methodology and findings are presented.

Several different methods are applied in a time-resolved manner to follow the lifetime of biomolecular 'coronas' both in situ and isolated from the excess plasma. The studies have shown that for many nanomaterial types, blood plasma-derived coronas are sufficiently long lived that they are likely to be what the cell sees.

The synthesis of new D-seco-C-nor-taxane derivatives in which the D-ring is deleted and the C-ring is transformed into a new pentatomic ring is performed starting from baccatin III derivatives. The formation of furanosyl or cyclopentyl rings is dependent on the presence of unprotected or protected oxygen at C-7 in the starting material and the reactions have proceeded with good diastereoselectivity with control of the stereochemistry of one or two stereocenters.

A study was conducted to gain insight into the self-assembly properties of a cholesteryl-tetraethylenglycol single stranded 18-mer oligonucleotide ([ON.sub.1]TEG-Chol) in aqueous solution and on its spontaneous insertion in fluid phospholipid membranes. The lipophilic oligonucleotide was found to be a suitable building block that could effectively serve as a hydrophobic anchor in the fluid bilayer to assemble supramolecular constructs based on the DNA digital code.

The study employs the technique of sum frequency generation (SFG) imaging microscopy to analyze the reactions taking place between cyanide and gold at the solid-liquid interface. The continuous exposure of the gold film to cyanide is shown to lead to the formation of higher-coordinated gold-cyanide complexes.

The consequences of a pure electrolyte at the interface in an electrochemical system are presented. It was noticed that all techniques were measured as a function of applied potential to give complete description of the interface for numerous imidazolium-based ionic liquids.

Sum frequency generation vibrational spectroscopy is used for studying the gas-liquid interface of room-temperature ammonium and pyrrolidinium ionic liquids. The chain length dependence studies have shown that the contribution of the N[C[H.sub.3] vibration is masked by the chain for lengths of four carbons and more.

The aggregation behavior of different 1-R,2-R-sn-glycero-3-phosphatidyl-nucleosides, where R = 8 (Di[C.sub.8]PN) or R = DLPN and N is either adenosine or uridine, a complementary pair in RNA) is compared. The nucleic functionalization has provided an additional parameter to control self-assembly through specific interactions among the polar heads and have altered the aggregation thresholds.

An ordered lamellar phase of type [L.sub.[alpha].sup.c] is formed without any mediation from divalent cations in order to study nucleic acid/nucleolipid complexes. Polynucleotides bind to small like-charged globular micelles and this behavior is present even in different suprastructures as bilayer membranes from long-chain derivatives.

Sum frequency generation vibrational spectroscopy is used for studying the orientation of the cation and the anion of room-temperature ionic liquids. The results have shown that presence of both ionic species at the gas-liquid interface and have described the behavior of a simple inorganic anion at the surface.

The surface orientation of ionic liquids, 1,3-dimethylimidazolium methyl sulfate, [MMIM][MS], 1-ethyl-3-methylimidazolium methyl sulfate [EMIM][MS], and 1-butyl-3-methylimidazolium methylsulfate, [BMIM][MS] at the gas-liquid interface was determined. The observations exhibited that both ions are present at the first layer of the gas-liquid interface and the alkyl chains are extended towards the gas state and far away from the liquid state.