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The synthesis, structure and magnetic properties of (A)[[Fe.sup.III](ox)[Cl.sub.2]] (A = [Et.sub.3]N[H.sup.+], [Me.sub.4][N.sup.+], and N-[Bu.sub.4][N.sup.+], ox = oxalate), are presented. The long-range magnetic ordering is attributed to the dipolar interaction between the chains separated by cations over the large distance.

Mono and diprotonated species of [[I[Mo.sub.6][O.sub.24]].sup.5-] were synthesized and structurally characterized. These protonated species react with methanol in a selective manner to give methylated Anderson-type anions while the unprotonated [[I[Mo.sub.6][O.sub.24]].sup.5-] anion does not react with methanol under similar conditions.

Five novel metal pamidronate (3-ammonium-1-hydroxypropylidene-1,1-biphosphonate, APD) complexes are hydrothermally synthesized under similar conditions, whose structures span zero, one, two and three dimensions on the basis of the different binuclear secondary building units (SBUs) and different coordination modes of APD. The solid-state emission spectra of the five compounds are measured, and their photoluminescence properties indicate that the introduction of different metal ions can enhance or weaken the intraligand transitions of APD.

A novel three-component synthesis of 5-aminooxazole and its subsequent one-pot triple domino transformation to pyrrolopyridine is described. The observed beneficial effect of ammonium chloride may be a general phenomenon and should find application in designing novel multicomponent reaction based on the isonitrile chemistry.

An easy one-pot room-temperate keto-group oxidation of a condensed heterocyclic system in a metal-(bis)dithiolene complex matrix is described. This oxidation from [[ODP].sup.2+] to [[ODP].sup.t+] in [[ODP].sub.2][Ni[(mnt).sub.2]] compound is a rare example of a metal-dithiolene system that caused an otherwise difficult oxidation at one of its component (cation) and exhibits emission in the visible region it room temperature.

A study was conducted to show that not only electronic properties but also the shape of anions could account for their influence on the interaction between cation and a synthetic host. The result showed the complex formation involves interaction of the whole ion pair with the host indicating that steric requirements of the anion influence complex geometry and stability.

A wide variety of different linear, diquaternary alkylammonium ions are used as supplementary crystallization structure-directing agents (SDAs) to synthesize the a high-silica version of zeolite erionite, UZM-12. The results demonstrated the detrimental effect of the nanocrystallinity of series of H-UZM-12 zeolites on the activity and stability of the reaction possibly due to the fast buildup of large coke molecules on the external surface of zeolite crystallites that inhibited the methanol diffusion to intrazeolitic acid sites, rendering them ultimately inaccessible for catalysis.

The [1,2] and [2,3] migration steps in the Stevens and Sommelet-Hauser rearrangements occurring in the yields of quaternary ammonium salts are analyzed at M05-2x levels. The most vital factor determining the extent of competition with the Stevens rearrangement is shown to be the difference in the reaction energies as the formation of the Sommelet-Hauser intermediate is less endoergic.

The pore volume and BET surface area of bio-MOF-1, [Zn.sub.8][(ad.sub.4])[(BPDC).sub.5]O.2[Me.sub.2]N[H.sub.2], is modified via postsynthetic cation exchange with either tetramethylammonium, tetraethylammonium or tetrabutylammonium cations to yield [Zn.sub.8][(ad).sub.4][(BPDC).sub.6]O.2[Me.sub.4]N, [Zn.sub.8][(ad).sub.4][(BPDC).sub.6]O.2[Et.sub.4]N, and [Zn.sub.8][(ad).sub.4][(BPDC).sub.6]O.2[[Bu.sub.4]N. The impact of pore volume and BET surface area on C[O.sub.2] capacity is analyzed and it is shown that materials with intermediate porosity have the largest C[O.sub.2] capacities under the conditions.

Synchrotron X-ray diffraction and reverse Monte Carlo simulation are used for studying the effect of addition of tetraethylammonium tetrafluoroborate on the structure of propylene carbonate (PC) confined in slit-shaped carbon nanopores of activated carbon fiber. PC molecules have accepted these ions efficiently and the structural modulation function of PC molecular assemblies has contributed to the evolution of supercapacitance in carbon nanopores.

The application of the transition state analogue inhibitor 4-aza-eudesm-11-ene is described to explore the intermediacy of eudesmane cation as an on-path intermediate in the biosynthesis of aristolochene from Penicillium roqueforti (PR-AS). Ammonium ion in 4-Aza-eudesm-11-ene as the hydrochloride salt appears to act as a genuine mimic of eudesmane cation that most likely binds the active site of PR-AS in a productive conformation resembling that adapted by eudesmane cation during the PR-AS-catalyzed synthesis of bicyclic sesquiterpene (+)-aristolochene.

The secondary terephthalamide host 1a-H attached to four aryl blades is prepared from tetrabromide by Suzuki-Miyaura coupling and has undergone a conformational change from a nonpropeller anti-form to a propeller-shaped syn-form upon complexation with ditopic guests such as p-xylylenediammonium derivatives (R,R)/(S,S)-3. The chirality generation-chirality biasing protocol is applied to a neurotransmitter, (-)-phenylephrine, which has acted as a chiral ditopic guest.

The targeted design and simulation of a new family of zeolitic metal-organic frameworks (MOFs) based on benzenedicarboxylate (BDC) as the ligand and [epsi]-type Keggin polyoxometalates (POMs) as building units, named as Z-POMOFs is reported. The electrocatalytic reduction of bromate demonstrated the application of the maintained electrochemistry of the [epsi]-Keggin POM in the insoluble Z-POMOF1 framework.

The synthesis and characterization of single-walled carbon nanotubes (SWNTs) filled with a zinc-containing quaternary ammonium based ionic liquid (ChZnCl3) inside is reported. The versatility of ionic liquids and the unique phase transition observed inside the SWNTs provide a new opportunity for modulation of the electronic properties of carbon nanotubes.

The synthesis of receptor 2,6,10,14,18-pentaaza[20]-21,34-phenanthrolinophane (L1), containing a pentaamine chain linking the 2,9 positions of a phenanthroline unit, is reported. The potentiometric, [super 1]H NMR, and spectrofluorimetric measurements offer insight into the protonation features of L1 and of receptor 2,6,10,14,18,22-hexaaza[23]-24,37-phenanthrolinophane (L2) and the fluorescent emission of both receptors which depended on the protonation state of the polyamine chain.

The application of the various supramolecular synthons for the synthesis of a new series of low molecular mass organic gelators (LMOGs) derived from simple organic salts. A new approach for the instant gelation of various different organic fluids at the room temperature is also presented.

A study was conducted to investigate how quaternary organic ammonium ion, benzyltriethylamine (BTEA), adheres to the Na,K-ATPase to produce membrane potential dependent inhibition. Findings revealed that information about electrogenic ion binding reactions of the Na,K-ATPase are not directly measurable during ion transport by this enzyme.

The influence of the substitution of novel cyclization/fluorination reaction of N-dienes in superacid on superelectrophilic character of dicationic intermediates was explored to determine their effect on the synthesis of fluoropiperidines. The newly obtained dicationic [alpha]-chloronium ammonium intermediates starting from halogen-substituted dienes were applied to synthesize high-valued fluorinated piperidines.

The first efficient synthesis of 5-taurinomethyluridine [T m.sup.5]U and 5-taurinomethyl-2-thiouridine [T m.sup.5][s.sup.2]U and their physicochemical properties are described. The synthesis of modified ribonucleosides involved the reaction of 5-substituted uridine derivatives with a tetrabutylammonium salt of taurine that is highly reactive and well-soluble in common organic solvents.

The crystallization and solid photochemistry of six quaternary ammonium salts of 2,4-di-p-carboxyphenyl-2,4-dimethyl pentanone is reported. The salt formation resulted in solids with different melting temperatures and crystallinities, while photochemical excitation in the solid state resulted in the chemoselective formation of a single product arising from the homolytic loss of CO followed by combination of the intermediate radical pair.

The photoisomerization of terminal (E)-[alpha]-methylstilbene units of dialkylammonium salts in the presence of the crown ether dibenzo[24]crown-8 (DB24C8) was used to synthesize two [2]rotaxanes, each having a (Z)-[alpha]-methylstilbene unit as one of its stoppers. The obtained rotaxanes are found to be stable at room temperature, but dissociate slowly to their two components at elevated temperatures.

Ammonium salts are used as reagents in the Cu-catalyzed three-component reaction with terminal alkynes and sulfonyl or phosphoryl azides leading to N-protected amidines. The amidines bearing 2-bromobenzenesulfonyl moiety are efficiently catalyzed by the Cu-catalyzed intramolecular N-arylation to give an important pharmacophore skeleton of 2H-,1,2-4-benzothiadiazine 1,1-dioxides.

An efficient active transport that is energized by a simple one-shot acylation reaction of [2]rotaxane is described by providing the appropriate potential surface on the axle component. The series of the wheel movement controlled by the neopentyl group is shown to be the basic motion of the unidirectional linear molecular motor.

A very simple and efficient method is described to perform highly chemoselective reduction of aromatic nitro compounds to corresponding amino derivatives by using Cu nanoparticles and ammonium formate. The reduction could also be carried out by wide variety of other reducible functional groups in the molecules such as Cl, I, OC[H.sub.2]Ph, NHC[H.sub.2]Ph, COR, COOR, and CN.

The catalytically active species formed in the reaction of the first row transition metal ions such as [Co.sup.2+], [Ni.sup.2+], and [Cu.sup.2+] with ammonia-borane hydrolyze ammonia-borane to generate hydrogen are described. The results obtained demonstrated the deployment of stable first row transition metal catalysts for the generation of [H.sub.2] from AB via hydrolysis.

The hydrothermal synthesis of two microcrystals, [(N[H.sub.4]).sub.2]Th[(P[O.sub.4]).sub.2].[H.sub.2]O and N[H.sub.4][Th.sub.2][(P[O.sub.4]).sub.3] by using Th[(N[O.sub.3]).sub.4]-CO[(N[H.sub.2]).sub.2]-[H.sub.3]P[O.sub.3]-[H.sub.2]O system is reported. These are the first three-dimensional ammonium-thorium phosphate compounds structurally characterized by using X-ray power diffraction data.

The development of new temperature-controlled one-pot synthesis of substituted pyridine derivatives via [5C + 1N] annulation of 1,1-bisalkylthio-1,4-pentanedienes and ammonium acetate is reported. The method can be used to obtain pyridine derivatives in good to high yields attributed to the characteristics of 1,1-bisalkylthio-1,4-pentanedienes.

The study about the anion binding properties of two isomeric ammonium boranes, [p-(Me[S.sub.2]B)[C.sub.6][H.sub.4](N[Me.sub.3])] and [o-(Me[S.sub.2]B)[C.sub.6][H.sub.4](N[Me.sub.3])] cations is presented. The structural and computational studies reveal that both steric and electronic effects contribute to the unusual selectivity displayed by these cationic boranes.

Studies to show that nanoscale hexagonal supercrystal phase observed in distearoylphosphatidylcholine (DSPC) supported bilayers is dependent on the amount of dioleoyltrimethylammonium propane (DOTAP) in the bilayer were conducted.

Thermochemical parameters of the closo boron hydride [B.sub.n][H.sub.m.sup.2-] dianions, with n = 5-12, the [B.sub.3][H.sub.8.sup.-] and [B.sub.11][H.sub.14.sup.-] anions, and the [B.sub.5][H.sub.9] and [B.sub.10][H.sub.14] neutral species predicted by high-level ab initio electronic structure calculations is presented.

The mechanism of the oxidation of primary and secondary alcohols by the oxoammonium cation derived from 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) is investigated computationally at the B3LYP/6-31+G level, along with free energies of solvation. The reaction involves formation of a complex between the alkoxide anion and the oxoammonium cation in a pre-oxidation equilibrium wherein methoxide leads to a much larger formation constant than isopropoxide.

The spontaneous conversion of spherical vesicles of octyltrimethylammonium perfluorooctanoate (OTAPFO) into isolated polyhedral faceted vesicles is reported. The new polyhedral structures are found to be smaller by an order of the magnitude, as compared to the ones reported earlier.

Adamantlyammonium (ADN[H.sub.3]) was complexed with [18]crown-6 to form a supramolecular cation of (ADN[H.sub.3])([18]crown6) and introduced into a [Ni[(dmit).sub.2]] salt as a supramolecular rotor. The cation layer were alternately arranged with [Ni[(dmit).sub.2]] layers in the crystal in which the molecular rotation of (ADN[H.sub.3])([18]-crown-6) was confirmed from the temperature-dependent solid state H NMR.

A convenient and safe method for the synthesis of ammonia triborane and the studies of its hydrolytic hydrogen-release properties that indicate it is a promising new material for chemical hydrogen storage applications are reported. The real utility of the process as a chemical hydrogen storage system would depend on the development of new 'off-board' methods to regenerate ammonia triborate from these borates.

The first evidence of the existence of ammonia oxide [+.sup.N]H3[O.sup.-], the zwitterionic tautomer of hydroxylamine, in the condensed phase, in the shape of a crystal structure containing equal amounts of [+.sup.N]H3[O.sup.-], the zwitterionic tautomer and [I.sup.+] is reported. The structure of ammonia oxide presents the missing benchmark for computational work and important new evidence relevant to the exceptional reactivity of hydroxylamine.

A systematic study of the magnetic properties and single-crystal X-ray structure of tetramethylammonium manganese trichloride (TMMC) is carried out at various pressures in a novel approach towards the build up of structure-property relationships in a rapid, facile manner. The extent to which the structural phase transitions influence the magnetic behavior of the system and whether this limits the choice of model systems for future variable-pressure-temperature studies are described.

Two different methods are used to calculate the spectra of deuterated analogues to CH(sub 5)(super +) at various stationary points on the potential surface. The predicted spectra for CH4D(super +) and CHD4 contain features associated with the single D or H atom being preferentially located in one of the bonding sites.

The syntheses, structure and inclusion properties of trinuclear boron compounds having a calix-like shape are described. X-ray diffraction analysis reveals that diverse conformations, namely cone-cone and cone-partial cone, are possible due to the presence of two different units of aromatic rims and the inclusion properties toward primary amines and ammonium chlorides are analyzed.

The formation, characterization and complexation properties of the whole family of partially O-methylated p-tert-butyl[3.1.3.1]homooxacalixarene are described. The trends observed in the binding and in the selectivity of the strictly related hosts are analyzed on the basis of the varying importance of intramolecular hydrogen bonding and its effects on the conformation of the free and of the complexed ligands.

Synthesis of new energetic salts (2, 3, 5, 6, 13, 14, 21, 22) was done via the quaternization of derivatives of N-aminoazoles with nitric or perchloric acid or with iodomethane followed by metathesis reaction with silver nitrate or silver perchlorate. Single-crystal X-ray analysis confirmed the structure of 2-amino-4,5-dimethyltetrazolium nitrate (21).

Interaction of salmon sperm DNA (300-500 bp) and ultrahigh molecular mass DNA (166 kbp) from bacteriophage T4dC with linear poly(N-diallyl-N-dimethylammonium chloride) (PDADMAC) and slightly cross-linked (#) PDADMAC (#PDADMAC) hydrogel in water are studied. It is found that the linear polycation induced compaction of either native (double-stranded) or denatured (single-stranded) DNA by forming PDADMAC-DNA interpolyelectrolyte complexes (IPEC)s.

The magnitude of the stabilizing interactions between an aliphatic C-H bond attached to an ammonium nitrogen and a carbonyl oxygen is evaluated by ab initio calculations at the MP2/6-311++G level of theory. Results reveal that R3N(super +)- C-H...O=C is the strongest hydrogen bond of the C-H...O type known to date.

The influence of deuteration on the crystal structure of the ammoniumzinc(II) Tutton salt and its deuterated analogue is studied. Results suggest, when the structures are compared at 298 and 110 K, then the Zn(H2O)6(super 2+) ions experience a slightly stronger compression along the Zn-O(9) direction and that the strains along Zn-O(7) and Zn-O(8) are nearly equal at 298 K than at low temperatures.

A novel noncovalent method is reported to immobilize a protein on a solid surface using the cucurbit[7]uril-ferrocenemethylammonium (CB[7]-FA) pair. Along with this, the immobilization of ferrocenylated glucose oxidase on a CB[7]-anchored gold substance and its use as a glucose sensor is also demonstrated.

The use of a threading-followed-by swelling protocol to synthesize molecular rotaxanes by the modification of 'oxygen deficient' macro-cycle I/dibenzylammonium ion molecular recognition system is described. Results demonstrate that achiral molecular rotaxanes could be synthesized by such a protocol.

A simple solution route is developed to hydrogen terminated silicon nanoparticles. Macroscopic amounts of powder can be obtained of either crystalline or amorphous nanoparticles, depending upon solvent and reaction conditions like temperature less than 300 degree Celsius.