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Different decouplings of the electron propagator were employed to provide theoretical comparison to experimental electron detachment energies for the pyrrolide, imidazolide, and pyrazolide anions. The ab initio electron propagator results were found to be in close agreement with experimental values, and the associated Dyson orbitals provide a detailed catalog of bonding changes as the number and positions of N atoms vary within the set of pentagonal aromatic anions.

Four effects providing overlimiting current transfer in ion-exchange membrane systems are investigated. The electrochemical behavior of homogeneous and heterogeneous membranes under conditions favorable and not favorable for gravitational convection is considered and the behavior of two membranes with the same surface morphology but with different ability to split water is compared.

The study of properties of aromatic anion species, which is of fundamental importance, is carried out, to understand the relationships between proton transfer in self-assembled monolayers on metal surfaces and nonlinear optical properties in solution and in crystals. Results of polarizabilities of aromatic anions have shown that benzenesulfinate is an anion with exceptional values for beta and that the benzenethiolate shows large values of gamma compared with the rest of anions.

The molecular structures, electron affinities, and dissociation energies of the Si(sub n)H (n= 4-10) species is examined. The basic set is of double-xi plus polarization quality with additional diffuse s- and p-type functions, denoted DZP++.

The effects of properties of the polypeptide and anionic reactant on the nature of the reaction products are investigated. It is observed that polypeptides composition, sequence, and charge state can play a notable role in determining the distribution of products.

The reorganization energies between the neutral molecules and the corresponding monoanions for cyanodienes are larger than those for acenes with D2h geometry and the single transfer through cyanodienes is discussed. The structures of the monoanions of cyanodienes are optimized under D2h geometry, and the vibronic interaction effects in the monoanions of cyanodienes are described.

The synthesis, structure, and magnetic properties of two new tetranuclear Cu(II) complexes containing N,N,N',N'- tetraethylpyridine-2,6-dithiocarboxamide (S-dept) of formula [Cu2Cl2(mu-S-dept)2]Cu2Cl4(mu-Cl)2] and [Cu2(mu-Cl)2-(S-dept)2][CuCl3(EtOH)]2 are reported. Their X-ray crystal structures reveal that the complexes are composed of anionic and cationic dimers.

The influence of the electronic effects on the enantioselectivity of the oxazaborolidine-catalyzed asymmetric borane reduction of ketones is examined and the utility of the robust catalyst is extended for the preparation of secondary alcohols with a variety of functional groups. Experimental findings disclosed that soluble coordinateable anions in the reductive system greatly affect the enantioselectivity especially for the beta-methoxy catalyst because of their coordination with the boron atom in the catalysts.

High-level calculation (G2+) is used to characterize the gas phase potential energy surfaces of the nonidentity proton transfer reactions of a series of simple anions (H (super -), CH (sub 3)(super -), NH (sub 2), OH (super -), F (super -), Si H (sub 3)(super -), PH (sub 2)(super -), SH (super -), C1 (super -), HCC (super -) and NC (super -) with their conjugate acids. The studies of the asymmetric proton transfers indicate that the surface take on a shape that is a hybridization of the shapes of the parent, symmetric proton transfers.

The studies was conducted to calculate the complexes formed by variety of anions with perfluoro derivatives of benzene, napthalene, plyridine, thiophene and furan using DFT (B3LYP/6-31++G(super **) and MP2)6-311++G(super **)) ab initio methods. The AIM analysis of the electron density showed a variety of topologies depending on the aromatic system considered.

Electron paramagnetic resonance (EPR) studies reveal that the steric interaction between the methyl hydrogens on a tert-butoxy substituent and the cyclooctatetraene (COT) ring system sterically induces a puckering of the eight-membered ring in the anion radical of tert-butoxy-COT. The conclusion suggests that the alkoxy-COT anion radical system, having a narrower and lower barrier, is more susceptible to tunneling than is [4]annulene.

A systematic XRD/FTIR/CHN/ICP investigation for the structural transformation of hydrotalcite-like compounds Mg(sub 1-x)Al(sub x)(OH)(sub 2)(NO3)(sub x).nH2O as a continuous function of nitrate anions is presented. The abrupt structural changes could be caused due to the drastic change in nitrate anion arrangement even though the nitrate anion maintains its D3h symmetry.

A configurational change was predicted for the adenine-imidazole complex upon dipole-bound attachment of an excess electron to this system. The presence of the electron reverses the stability order of the two lowest energy configurations of the complex.

A configuration landscape was predicted for dipole-bound (DB) anions of [adenine-(water(sub N))] complexes for N = 1, 2, and 3 using ab initio calcualtions. The study shows that hydration of adenine changes its long-range interaction with excess electrons, due to either reduction or enhancement of the dipole moment.

Simple calixpyrrole macrocycles, which provide an easy-to-synthesize example of an anion-binding agent, are presented. The method, which involves the purification of the crude product by following the utilization of thin-layer chromatography and recrystallization, helps reinforce the utilization of such commonplace organic chemistry techniques with respect to a useful synthesis while remaining within the time constraints of a typical organic laboratory.

The studies have shown that a rigid dicobalt(II) cryptate [[[Co.sub.2]L].sup.4+] has recognized [Cl.sup.-] and [Br.sup.-] but not [F.sup.-] and [I.sup.-]. The increase in the rigidity of a cryptate has improved its selectivity to anions and hence [[[Co.sub.2]L].sup.4+] is used as an efficient colorimetric sensor for [Cl.sup.-] and [Br.sup.-].

Anions of lithium battery salts were explored using electronic structure calculations with the objective to find a computational measure to correlate with the observed (in)stability of nonaqueous lithium battery electrolytes versus oxidation often encountered in practice. It was observed that accurate prediction of intrinsic anion oxidation potentials could be made by computing the vertical free energy difference between anion and neutral radical and further strengthened by an empirical correction using only the anion volume as a parameter.

The structures, energetic and vibrational frequencies of nine hydrogenated 9H-keto-guanine radicals [(G+H).sup..] and close shell anions [(G+H).sup.-] are predicted using B3LYP density functional method. The results show that the energetic order for the anions differs from that of the analogous radical, the [(G+H).sup..] and [(G+H).sup.-] readily exists as the products of consecutive electron attaching to [(G+H).sup.+].

The molecular structures, electron affinities and dissociation energies of the [Si.sub.5][H.sub.n.sup.-]/[Si.sub.5][H.sub.n.sup.-] (n=3-12) species were calculated by means of three density functional theory (DFT) methods. The different types of the neutral energy separations are the adiabatic electron affinity, the vertical electron affinity and the vertical detachment energy.

The molecular dynamics simulations were performed to investigate the key concern related to the ultrafast infrared spectroscopic experiments for OH frequency for HOD molecules in the hydration shell of the [I.super.-] ion solution system. An argument is made to the effect that the long modulation time related to the spectral diffusion of the OH frequency should be interpreted as showing the escape time of an HOD from the first hydration shell of the [I.super.-] ion.

Detailed studies on the binding of a series of cyclopeptide based receptors to sulfate or iodide show that binding affinity is not only due to the direct interactions between receptor and guest but also due to interactions within the receptor that do not directly involve the guest. While such reinforcement of molecular recognition through intra-receptor interactions is known to occur in some proteins, this is the first example of a synthetic receptor for which this mechanism is demonstrated.

A demonstration that neutral and cationic rhenium tricabonyl fragments promote the coupling of acetonitrile and either pyrazole or 3,5-dimethylpyrazole to afford complexes of the chelating pyrazolylamidino ligand is presented. By carefully choosing the reaction conditions, either these coupling products or the uncoupled pyrazole nitrile complexes could be obtained.

The study describes a new receptor cyclen capable of strong selective binding of pyrene-based anionic dyes under near-physiological conditions. This receptor comprises four naphthylthiourea groups tethered to a cyclen core through an ester linkage.

A new polar intermetallic phase, Li2Y5In9, is synthesized and structurally characterized. Its structure features a corrugated 2D In9 anion layer, in which two distinct types of square pyramidal In5 units are bridged by novel butterfly In4 clusters.

Two isostructural compounds Na3MIn2 with a NiTi2-type structure are synthesized through typical high-temperature reactions. On the basis of TB-LMTO-ASA calculations, the electronic structure of both compounds reveals substantial participation of sodium in the overall bonding of the structure.

The evidence for the cluster of positively charged residues, Arg-98, Lys-99, and Lys-100, to constitute a hot spot for binding anionic lipid is provided. It is observed that single mutations of the charged residues do not result in a gain of function phenotype.

Resonance Raman spectra of the anion radical and dianion of a free-base porphycene were obtained and quantum chemical calculations based on the density functional theory methods was carried out in order to derive the force fields of porphycene anions. Normal modes with similar vibrational characteristics were correlated by examining the overlaps between the different redox states in order to characterize the frequency shifts measured for reduced porphycenes in certain skeletal vibrational modes.

The juxtaposition of carboxylate groups with the benzene ring is investigated to identify superhalogens and intrinsically stable dianions and trianions. The organic species are studied in which F atoms replace H atoms because inorganic superhalogens often contain F atoms that were considered a likely procedure for identifying anions with large electron detachment energies.

Proper and improper hydrogen bonds in metalloorganic crystal architecture are reported. In some cases the effect of hydrogen bond was also shown by the vibrational pattern of the anions.

Dynamic combinatorial chemistry can be used to optimize the binding properties of bis-(cyclopeptide) 2 toward anions in aqueous solution. Results demonstrate that dynamic combinatorial optimization of designed receptors can be a useful strategy, bringing synthetic receptors with efficiencies approaching those of proteins one step closer.

It is shown that the 3.1 kcal/mol instability of the zwitterion form of neutral arginine in the gas phase relative to the canonical tautomer is suppressed by attaching an excess electron. The solvation by an excess electron provides an extra stabilization of 7.3 kcal/mol for the zwitterion structure and only 3.7 kcal/mol for the canonical structure, hence the anions based on the zwitterionic and canonical structures become quasidegenerate with their electronic energies differing by less than 0.4 kcal/mol.