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The dielectric constant [Epsilon] and conductivity Σ of undoped [C.sub.60] single crystals have been measured as a function of temperature, 10 K < T < 330 K, and frequency, 0.2 kilohertz < f < 100 kilohertz. On cooling below the first-order structural phase transition at 260 K, a Debye-like relaxational contribution to the dielectric response is observed, which requires the presence of permanent electric dipoles. The relaxation rate is thermally activated with a broad distribution of energies centered at 270 millielectron volts. The existence of a dipole moment in [C.sub.60] is unexpected, because it is precluded by symmetry for the pure ordered cubic phase. These data suggest that the high degree of frozen-in orientation disorder of the [C.sub.60] molecules for the existence of electric dipolar activity., The discovery and synthesis of the icosahedral carbon molecule [C.sub.60] [1] and its subsequent crystallization [2] have stimulated great gravity directed toward understanding the static and dynamic properties of its [...]

The bistatic radar scattering cross section (BRSCS) of a chaff cloud is investigated in the ground-based system for arbitrarily polarized transmitters and receivers. Chaff wire orientations uniformly random in space, as well as uniform in azimuth and Gaussian in elevation, are considered and the effects on the cross section are also discussed.

The fast Fourier transform (FFT) is used in conjunction with analytical techniques to obtain an approximate expression for the Sommerfeld integral associated with a vertical electric dipole above a half-space. The resulting expression, which is an analytic function of the source and observation locations, can be used in lieu of a numerical integration of the Sommerfeld integral. It can be used in either the near zone or the far zone, and it can even be applied for observation angles close to grazing. The accuracy of the expansion directly depends on the number of terms used in the fast Fourier transform. Results obtained using the expansion are compared with those obtained both from a direct numerical integration of the Sommerfeld integral and the reflection coefficient method.

Expansions of the volume integrals of strongly localized, continuous, differentiable electric charge and current densities are introduced in terms of the total charge, and variable and moving electric and magnetic dipoles, and conditions under which such expansions are applicable are determined. To enhance an understanding of the effects of external electromagnetic fields acting on very localized densities of electric charges and currents, the resulting Lorentz force, torque, and power are computed by using such expansions. To show how versatile variable and moving dipoles are for building physical models, the following are considered: (a) energy conversions by electric motors, by dielectric and induction heating, and by the magnetic drag force, and (b) relativistic effects in translational movements of steady electric and magnetic dipoles; in particular, the torgue on a magnetic dipole moving parallel to a line carrying a steady current and uniformly distributed electric charges.

Sensitive experiments have been developed that search for electric dipole moments of atoms, molecules, and the neutron. These experiments play an important role in deciding which of the myriad theoretical [...]

It is demonstrated that d-dimensional uniaxial systems with both short-range ferromagnetic interactions and long-range dipole-dipole interactions have d(sub c) = 3 as the upper marginal dimension above which mean-field behaviour fully begins. The method used in this research derives the result for any d without any constraints.

The generalized Mulliken-Hush approach cannot be used to solve the inverse problem in the study of electronic transfer since the method assumes that the diabatic states are so well localized that the corresponding off-diagonal diabatic dipole moment is equal to zero. A general formula for the adiabatic-to-diabatic mixing angle that takes into account non-zero off-diagonal diabatic dipole moment is presented. The formula is also useful for perturbation estimations when the off-diagonal diabatic dipole moment is small enough.

The communication presents numerical results in the form of a comparison of predictions due to a numerical algorithm using a previously published exact nonlocal Absorbing Boundary Condition (ABC) and analytical results for the field radiated by an infinitely small dipole. The numerical approximations are derived, and application to the FDTD method is straightforward. The method is compared to a related approach due to De Moerlose et al., and it is shown that the method yields better accuracy since higher order interpolation and numerical integration schemes may be used with this formulation.

Analysis of a model in which interdiffusion with Cu causes a reduction of moments on the Ni atoms in the Ni/Cu interface explains the magnetic structure of Ni/Cu and permalloy/Cu interfaces in sputtered spin value magnetoresistive layered structures. The moments, however, persist at the permalloy/Cu interface and will be disordered at finite temperatures, as suggested by first principle total energy measurements. The reduced or disordered moments might markedly diminish the giant magnetoresistance.

A new methodology for making quantitative micromagnetic measurements of the in-plane moment canting in Fe-based amorphous alloys, via polarized Mossbauer spectroscopy, is introduced and explained. The technique is applied to the measurement of the approach to magnetic saturation of a field-annealed [Fe.sub.78][B.sub.13][Si.sub.9] ribbon. It is demonstrated that even in a field of 200 k[Am.sup.-1] the moments are not completely saturated, and are canted by on average [approximately] 3 [degrees] to the applied field.

This paper describes methods permitting the determination of the magnetic dipole moments of volume microdefects in thin films with a perpendicular anisotropy. The methods are based on the study of solitary defect interactions with a stripe domain, a flat wall in a gradient magnetic field, and with a bubble. Mathematical models of these interactions are developed and realized with computer. Magnetic moment magnitudes are determined for the attractive and repulsive defects in the garnet films. Results obtained by means of various methods agree within 30%.

The macromolecular technique of calculating the dipole moment of particles in a mixture, such as an artificial magnetodielectric (AMD) material, is quite general and also computer intensive. The conjugate gradient (CG) method has proven to be an efficient solver for equations resulting from the macro-molecule formulation. The conjugate gradient solver presented here has been applied to an electric and magnetic dipole problem with coupling of the dipole moments. The CG method is compared to other solvers for this application.

The effect of collective thermal fluctuations on the switching characteristics of a pair of identical uniaxially anisotropic dipoles was investigated. The results showed that thermal fluctuations had a reducing effect on the symmetry of the fanning reversal mode. Thermal agitation broke the symetry of the system and reduced the correlation in the trajectories of the two moments during the reversal process.

Pair interactions in the rare earth trifluoromethanesulfonates R(CF3SO3)3 9H2O were investigated. The results showed that there is a magnetic dipole moment along the c axis while an electric dipole moment developed in the perpendicular (xy) plane. Nearest-neighbor and next-nearest-neighbor interactions were of opposite sign, comparable magnitudes and were much larger than those of magnetic dipoles.

The influence of configuration fluctuation effects on the giant magneto-optic characteristics of anisotropic, magnetically ordered, highly-correlated f-electron materials was investigated. The results confirmed that band theory alone is not sufficient for elucidating key effects of interconfigurational fluctuations in correlated-electron systems.

An analytical model is developed for describing the interaction between rigid ammonia molecules including the explicit description of induction. The putative global minima for [(N[H.sub.3]).sub.n] (n = 3-20) are optimized by using this new model.

A model for solute-solvent electrostatic interactions in ionic liquid is described which provides screening of the solute electric field without polarization of the medium, solving a possible contradiction between the weakness of solute-solvent interactions and the behavior of a conductive system. The model forecasts the nature of the solute-solvent interactions in ionic liquids and it is consistent with the empirical data on testing.

Arbitrary superposition states of mixed multiplicity can be prepared by dynamic Stark shift using strong nonresonant pulses. A simple model is proposed to analyze the properties of spin transfer and sequential transfer and also the feasibility of their experimental implementation for spin-orbit transitions in [Rb.sub.2].

A new method is described for the preparation of polyaniline (PANI) by using aniline and oxidant solutions separated by a non-ionic semipermeable cellulose membrane. PANI is produced entirely on the aniline side of membrane, which is explained by the formation of a thin layer of PANI on the cellulose membrane that converts a cellulose membrane to a composite PANI-cellulose membrane.

A study was conducted to provide criteria for optical artifacts recognition in reflection-mode apertureless scanning near-field optical microscopy, implementing demodulation techniques at higher harmonics. The experimental results of the model predicts a lack of correlation between the topography and optical images even for structures a few tens of nanometers high, due to the rectification effect introduced by the lock-in amplifier used for signal demodulation.

A microrheological method is developed that is suitable for measuring the viscosity of ferrofluids by using oscillating non-magnetic spheres. The method is advantageous due to its small volume of fluid and is also applicable for fluids of low viscosity.

Electroabsorption spectra are produced for single-stranded polynucleotides poly(U), poly(C), poly(A), and poly(G) in glycerol/.water glass at low temperature, and the differences in permanent dipole moment ([Delta][mu]) and polarizability ([Delta][alpha]) are determined for various spectral ranges covering the lowest energy absorption band around 260nm. The electroabsorption data facilitates distinguishing a weak electronic transition associated with a wing in polynucleotide absorption spectra, at energy below the electronic origin in absorption spectra of monomeric nucleobases.

The frequencies and intensities of the hydrogen-bonded OH-stretching transitions in the water dimmer complex are calculated along with the investigation of the effects of counterpoise correcting the potential energy surface and dipole moment function. It is found that the effect of using a numeric potential is significant for higher overtones.

A detailed charge-charge flux-dipole flux (CCFDF) study of the difluoro- and dichloroethylenes is reported. It is observed that the CCFDF contributions are transferable from cis to the trans isomers providing accurate predictions of the theoretical trans intensities with rms errors of 8.6 km [mol.sup.-1] for difluoro- and 5.9 km [mol.sup.-1] for dichloroethylene.

The intermolecular dipole-dipole cross-relaxation is measured in the micellar solution of sodium perfluorooctanoate (NaPFO). The intermolecular cross-relaxation and aggregation-induced [super 19]F chemical shift changes have not indicated any direct water contact to fluorines except for those closest to the head group.

Rotational spectra are recorded for one conformational isomer of 1-phenyl-2-propanol, methamphetamine and 1-phenyl-2-propanone. Optimized ab initio models have identified these as the lowest energy conformations for each species.

The EPR spectroscopic studies of the cytochrome [b.sub.6]f complex have demonstrated that all signals above g = 4.3 are associated with a spin interaction between hemes [b.sub.n] and [c.sub.n]. The electronic coupling has implied that the heme [b.sub.n]/[c.sub.n] pair might function as a unit to facilitate 2-electron reduction of plastoquinone without generation of an energetically unfavorable semiquinone intermediate.

X-ray and ultraviolet photoemission spectrosocpies (XPS and UPS) are used to study the energy level alignment and electronic structure at the Co/pentacene/Co interfaces. The results of the deposition of the reactive Co on pentacene have indicated only a small penetration depth of the metal atoms into the pentacene layer and a complete band diagram is given for the layered Co/pentacene/Co structure.

Entire excited state deactivation of monomer 4-N,N-(dimethylamino)-4'-nitrotolane (DMNAT) and trimer, tris-4,4',4'-(4-nitrophenyleethynyl) triphenylamine (T-NPTPA) in different solvents using femtosecond transient absorption measurements is investigated. The results have unambiguously revealed that the charge-delocalized C3 symmetry state is the Franck-Condon (FC) state for trimer in all solvents.

A study presented the possibility of a molecule moving unidirectionally in an electric field of a polar periodic substrate as a result of the fluctuations of molecular dipole moment occurring on the photoexcitation of the molecule. As estimated for such motion, molecules with sufficiently long fluorescence and strongly differing dipole moments in the ground and excited states could move with an average velocity of the same order as that typical of protein motors such as kinesin.

The typical molecular wire, polyacetylene, which bridges two chemically inert electrodes was theoretically investigated at the Hartree-Fock level by incorporating the external electric field into the calculations. The results show that both the geometric and the electronic structures of the conjugated molecular wires are sensitive to the electric field, which reduces the highest occupied molecular orbital -lowest unoccupied molecular orbital gap and increases the dipole moment.

Stark absorption spectroscopy is applied to 6-hydroxyquninoline (6-HQ) doped in polymer films of poly (methyl methacrylate) and poly (vinyl alcohol) at a temperature rang of 50-300 Kelvin. The results reveal that the molecular motion of 6-HQ in a polymer is very sensitive to the microenvironment of the surrounding matrix.

A study explores the orientational dependence of plasmon coupling in assemblies of anisotropic plasmonic nanoparticles. Findings demonstrate that the solution assembly of nanorods induced by the addition of sodium citrate results in the blue-shift of the longitudinal nanorods plasmon band, and a red-shift of the transverse plasmon band.

A comprehensive study of the growth and fabrication of Bragg-spaced quantum well, a type of resonant photonic band gap structure is conducted. Results revealed that drift in the growth rate greater than a few percent leads to collapse of the resonant photonic band gap (RPBG), while random disorder of several percent leads to extra peaks in the RPBG due to coupling to the intermediate band.

Surface-assisted photoindcued transient displacement charge (SPTDC) technique was used to study charge transfer in self-assembled monolayers of 7-diethylaminocoumarin covalently linked to an oxide surface in the atmosphere of different gases. The dipole signal was found to be opposite to that in solution and dependent on the nature of the gas and its pressure and the effect is due to the collision-induced relaxation which prevents molecules from uninhibited tilting onto the surface.

Discrete dipole approximation (DDA) calculations, each of a distinctive morphology, are performed to demonstrate the specific ways in which shape affects the absorption and scattering of light. The control of nanostructure shape has allowed the optimization of plasmon resonance for molecular detection and spectroscopy.

Ultrasensitive searches are conducted for the axion, which is hypothetical particle with a mass possibly a trillion times lighter than an electron and exceedingly small coupling to ordinary matter. These searches might detect its presence, either as dark matter or as component of solar flux, which could ultimately improve on limits from interfaces based on solar evaluation.

The influence of the molecular orientation on the molecular electronic structure is studied on the Cu-phthalocyanine/graphite system via film thickness dependences of metastable-atom electron spectra and ultraviolet photoelectron spectra. The results show that the change in the molecular orientation is an important origin of the band-bending-like shift in the molecular electronic states even if the molecule has no permanent electric dipole.

Accurate equilibrium bond lengths are established for linear carbon chains of type Si[C.sub.n]O with n = 3-8 on the basis of Results of Coupled Cluster Calculations. It is demonstrated that the ground state rotational constants of Si[C.sub.3]O, Si[C.sub.4]O and Si[C.sub.5]O are predicted with ca. 0.1% accuracy.

A research addressing a comprehensive particle-based simulation study of the structural, dynamic, and electronic properties of the liquid-vapor interface of water utilizing both ab initio and empirical models is illustrated. Numerous properties such as interfacial width, hydrogen bond populations, dipole moments, and correlation times will be characterized with identical schemes to draw useful conclusions on the strengths and weakness of the proposed models for interfacial water.

Two important factors, which include the effective excited state coupling and transition dipole moment orientation, influence the observed features of the absorption and resonance Raman spectra for the di-p-anisyl hydrazine cation. The magnitude of the effective excited state coupling dictates the energy splitting between the two components of the absorption band assigned to the exited state mixed valence (ESMV) transition.

4-(Dimethylamino)-4'-cyano-1,4-diphenylbutadiene (DCB) and 4-(dimethylamino)-2,6-dimethyl-4'-cyano-1,4-diphenylbutadiene (DMDCB) are characterized spectroscopically. The strong difference in absorption and fluorescence solvatochromic slopes suggests that the simple Onsager model with a point dipole approximation is not sufficient.

A field theory is used to examine the forces underlying raft formation on resting living cell membranes. Experiments that could further assess the importance of dipolar interactions for lateral organization of the components on multiple length scales in membranes are suggested.

Simulations of the absorption efficiency using the discrete dipole approximation (DDA) method and taking into account the real shape of gold nanorods are reported. From the experimental point of view, good agreement with the published data for gold nanorods is obtained.

1,3-Dipolar additions of C(sub 60) with dipoles, diazomethane, nitrile oxide, and nitrone are modeled and their mechanism, regiochemistry, and nature of addition are investigated. C(sub 60) reacts with diazomethane, nitrile oxide, and nitrone to give fullereno pyrazolines and isoazolines and there are four types of additions possible, which are closed [6,6], closed [5,6], open [5,6] and open [6,6] that lead to corresponding adducts.

A polarization inversion spin exchange at the magic angle (PISEMA)-based pulse sequence modified to achieve selective measurement of dipolar couplings in amorphous phase is presented. (super 1)H-(super 13)C dipolar interactions are selectively measured by PISEMA-type sequence.

A brief description on the assigning IR vibrations from an H2O.O2 complex in an inert rare gas matrix is presented. A harmonically coupled anharmonic oscillator local mode model was used with an ab initio calculated dipole moment function to calculate the OH-stretching and HOH-bending frequencies and intensities in the complex.