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For the transition metal lithides ScLi and ScLi[+ or -], the adiabatic potential energy and the static and transition dipole moment curves of the low-lying electronic states in the representation [(2s+1) [[LAMBDA].sup.(+/-)) have been investigated. The spectroscopic constants, the electronic transition energy with respect to the ground state [T.sub.e], the internuclear distance [R.sub.e], the harmonic frequency [[omega].sub.e], the rotational constant [B.sub.e], the permanent dipole moment [[mu].sub.e], and the dissociation energies [D.sub.e] have been computed for the bound and excited states. Using the canonical function approach, these calculations have been followed by a rovibrational calculation from which the rovibrational constants [E.sub.v], [B.sub.v], and [D.sub.v] and the abscissas of the turning points [R.sub.min] and [R.sub.max] for the investigated bound states are calculated. A feasibility study of laser cooling of ScLi and its ions ScL[i.sup.[+ or -]] has been done. New 62 electronic states have been investigated in the present work for the first time. No useful cooling scheme was found for those molecules. Key words: ab initio calculation, electronic structure, spectroscopic constants, potential energy curves, dipole moments, Franck-Condon factor, radiative lifetime, laser cooling, 1. Introduction The theoretical and experimental studies of cold and ultracold molecules have been motivated by many applications, including ultracold chemical reactions, molecular spectroscopy, quantum computation, and molecular direct laser [...]

The control of molecules is key to the investigation of quantum phases, in which rich degrees of freedom can be used to encode information and strong interactions can be precisely tuned.sup.1. Inelastic losses in molecular collisions.sup.2-5, however, have greatly hampered the engineering of low-entropy molecular systems.sup.6. So far, the only quantum degenerate gas of molecules has been created via association of two highly degenerate atomic gases.sup.7,8. Here we use an external electric field along with optical lattice confinement to create a two-dimensional Fermi gas of spin-polarized potassium-rubidium (KRb) polar molecules, in which elastic, tunable dipolar interactions dominate over all inelastic processes. Direct thermalization among the molecules in the trap leads to efficient dipolar evaporative cooling, yielding a rapid increase in phase-space density. At the onset of quantum degeneracy, we observe the effects of Fermi statistics on the thermodynamics of the molecular gas. These results demonstrate a general strategy for achieving quantum degeneracy in dipolar molecular gases in which strong, long-range and anisotropic dipolar interactions can drive the emergence of exotic many-body phases, such as interlayer pairing and p-wave superfluidity. A strongly interacting gas of polar molecules is created by combining an electric field with two-dimensional optical confinement, enabling evaporative cooling and opening up the exploration of low-entropy many-body phases., Author(s): Giacomo Valtolina [sup.1] [sup.2] , Kyle Matsuda [sup.1] [sup.2] , William G. Tobias [sup.1] [sup.2] , Jun-Ru Li [sup.1] [sup.2] , Luigi De Marco [sup.1] [sup.2] , Jun Ye [...]

We investigate an orderly study of the adiabatic potential energy curves for 29 and 30 low-lying [sup.2s+1][[LAMBDA].sup.+/-] electronic states of the molecules MgLi and MgNa, respectively. The calculation has been done by using the complete active space self-consistent field followed by multi-reference configuration interaction with Davidson correction. For the investigated electronic states, the static and transition dipole moment curves are calculated along with the Einstein coefficients, the emission oscillator strength, the spontaneous radiative lifetime, the line strength, the classical radiative decay rate of the single-electron oscillator, the spectroscopic constants ([T.sub.e], [[omega].sub.e], [[omega].sub.e][x.sub.e], [B.sub.e], [R.sub.e]), and the equilibrium dissociation energy [D.sub.e]. By means of the canonical functions approach, the ro-vibrational constants [E.sub.v], [B.sub.v], [D.sub.v], and the abscissas of the turning points, [R.sub.min] and [R.sub.max], have been calculated for the considered electronic states up to the vibrational level v = 79. The Franck-Condon factors have been calculated and plotted for the transition between the low-lying electronic states of the two considered molecules. A good agreement is revealed between our calculated values and those available in the literature. Fifty new electronic states are investigated in the present work for the first time.Key words: ab initio calculation, electronic structure, spectroscopic constants, potential energy curves, dipole moments, Einstein coefficients, ro-vibrational calculation, Franck-Codon factor.Nous completons une etude systematique des courbes d'energie potentielle adiabatique pour 29 et 30 etats electroniques de basse energie des molecules MgLi et MgNa respectivement. Le calcul est fait en utilisant le champ auto-coherent d'espace actif complet avec une interaction de configuration multi-reference avec correction de Davidson. Pour tous les etats electroniques etudies, nous calculons les courbes de moment dipolaire statiques et de transition, ainsi que les coefficients d'Einstein, la force d'oscillateur d'emission, le temps de vie radiatif spontane, l'intensite de raie, le taux radiatif classique de l'oscillateur a un electron, les constantes spectroscopiques [T.sub.e], [[omega].sub.e], [[omega].sub.e][x.sub.e], [B.sub.e], [R.sub.e] et l'energie de dissociation a l'equilibre De. En utilisant l'approche des fonctions canoniques, nous calculons les constantes rovibrationnelles [E.sub.v], [B.sub.v] et [D.sub.v] et l'abscisse des points de retour [R.sub.min] et [R.sub.max], pour tous les etats consideres ici jusqu'au niveau vibrationnel v = 79. Les facteurs de Franck-Condon sont calcules et presentes graphiquement entre les etats de basse energie des deux molecules. Un bon accord est observe entre nos resultats et ceux apparaissant dans la litterature. Ce travail introduit pour la premiere fois 50 nouveaux etats electroniques. [Traduit par la Redaction]Mots-cles: calcul ab initio, structure electronique, constantes spectroscopiques, moments dipolaires, facteur de Franck-Condon., 1. IntroductionResearch in the fields of cold and ultracold molecules caused a revolution in physical chemistry and many-body physics. The vibrational and rotational motions of the molecules offer degrees of [...]

Dielectric relaxation behaviors of nicotinamide+1-propanol, benzamide+1-propanol, and nicotinamide+1-butanol dissolved in [C.sub.6][H.sub.6] at 0.990, 0.985, 0.980, 0.975, 0.970; 0.990, 0.985, 0.980, and 0.980 mol fraction [x.sub.j] of 1- propanol or 1-butanol at temperature 30 °C and 30,40,50, and 60 °C, respectively, are studied using the Debye model of binary polar-non-polar liquid mixture to predict double relaxation times [τ.sub.2] and [τ.sub.1] and dipole moments [μ.sub.2] and [μ.sub.2] from susceptibility measurement of concentration variation solution data under static and 9.385 GHz electric fields. Nineteen systems exhibit [τ.sub.2], [τ.sub.1] and [μ.sub.2] [μ.sub.1] [τ.sub.2] are found to increase with temperature for all the binary polar mixtures, whereas [τ.sub.1], most probable t0, and measured t from slope methods are almost the same. They agree well with the t reported by Higasi. The plots of τ.sub.2]-[x.sub.j] and [μ.sub.jk]-[x.sub.j] curves reveal solute-solute and solute-solvent molecular association through H-bonding, and variation of μ with t (°C) is noted from the j-t curve. The associational aspects are taken into consideration from theoretical [μ.sub.theo] from the standpoint of inductive, mesomeric, and electromeric effects within the polar groups of the molecules. The estimated Debye factor [τ.sub.fk]T/η and Kalman factor [τ.sub.fk]T/[η.sup.γ] reveal that the polar mixture obeys the Debye relaxation mechanism. Key words: binary mixture, dipole moment, double relaxation time, monomer. Nous etudions les comportements de relaxation dielectriques de nicotinamide+1-propanol, benzamide+ 1-propanol et nicotinamide+1-butanol en solution dans [C.sub.6][H.sub.6] a fraction molaire [x.sub.j] de 0.990, 0.985, 0.980, 0.975, 0.970 ; 0.990, 0.980 et 0.970 de 1-propanol ou 1-butanol a des temperatures de 30, 40, 50 et 60 °C respectivement. Pour ce faire, nous utilisons le modele de Debye pour melange liquide binaire polaire et non polaire, afin de predire les doubles temps de relaxation [τ.sub.1] et [τ.sub.2] et moments dipolaires [μ.sub.1] et [μ.sub.2]a partir de mesures de la susceptibilite de solutions variables en concentration sous champs statique et a 9.385 GHz. Dix neuf systemes possedent ici des valeurs pour [τ.sub.1], [τ.sub.2] et [μ.sub.1], [μ.sub.2]. Nous trouvons que [τ.sub.2] augmente avec la temperature pour tous les melanges binaires polaires, alors que la valeur de [τ.sub.1], la valeur probable de [τ.sub.0] et la valeur mesuree de τ ne changent presque pas. Nous obtenons un bon accord avec les valeurs rapportees par Higasi. Les courbes graphiques de [τ.sub.jk]-[x.sub.j] et [μ.sub.jk]- [x.sub.j] revelent une association moleculaire solutesolute et solute-solvant via des liaisons H, en meme temps qu'on note une variation de μ avec t (°C) a partir de la courbe de [μ.sub.jk]-t. Nous tenons compte des aspects associatifs dans une etude theorique ([μ.sub.theo]) basee sur les effets inductifs, mesomeres et electromeres a l'interieur des groupes polaires des molecules. Les estimes du facteur de Debye [τ.sub.jk]T/η et de Kalman [τ.sub.jk]T/[η.sup.γ] revelent que le melange polaire obeit au mecanisme de relaxation de Debye. [Traduit par la Redaction] Mots-cles : melange binaire, moment dipolaire, double temps de relaxation, monomere. PACS Nos.: 77.22.Gm, 72.80.Le, 77.22.d., 1. Introduction Dielectric investigations into polar liquids dissolved in non-polar solvents provide meaningful information on structural and associational aspect as well as formation of molecular complexes in a gigahertz electric [...]

The potential energy curves have been investigated for the lowest 54 electronic states in the [sup.2s+1][Λ.sup.(±)] representation of the molecule NaHe via the multireference configuration interaction method (MRCI) and second-order multireference perturbation theory (RPST2-RS2). The harmonic vibrational frequency, [ω.sub.e], the internuclear distance, [R.sub.e], the electronic energy with respect to the ground state, [T.sub.e], and the permanent dipole moment, μ, have been calculated. The positions of [R.sub.min] and [R.sub.max] and their minimum and maximum energies [E.sub.min] and [E.sub.max] with respect to the dissociation asymptote have been determined for the considered electronic states. The comparison of our investigated values to the theoretical and experimental data available in the literature shows a good agreement. Forty-three electronic states have been studied theoretically in the present work for the first time. Key words: ab initio calculation, NaHe molecule, potential energy curves, spectroscopic constants, and dipole moment. Nous etudions les 54 plus bas etats electroniques dans la representation [sup.2s+1][Λ.sup.(±)] de la molecule NaHe, en utilisant la methode d'interaction de configuration multi-reference (MRCI) et la theorie de perturbation multi-reference (RPST2-RS2). Nous calculons la frequence de vibration harmonique [ω.sub.e], la distance internucleaire [R.sub.e], l'energie electronique par rapport au fondamental [T.sub.e] et le moment dipolaire permanent μ. Nous determinons les positions de [R.sub.min] et de [R.sub.max] et leurs energies [E.sub.min] et [E.sub.max] par rapport a l'asymptote de dissociation, pour tous les etats electroniques etudies. Nos resultats sont en bon accord avec les valeurs experimentales et theoriques disponibles dans la litterature. Quarante trois des niveaux electroniques etudies ici le sont pour la premiere fois. [Traduit par la Redaction] Mots-cles : calcul a partir des principes premiers ou ab initio, molecule NaHe, courbes d'energie potentiel, constantes spectroscopiques, moments dipolaires. PACS Nos.: 31.10.+Z, 31.15.A-, 31.15.vn, 31.50.Df., 1. Introduction During the last two decades, experimental and theoretical studies of doped helium clusters have been developed into strongly expanding fields. These finite systems can be employed in quite [...]

The potential energy curves and dipole moments for the low-lying electronic states of the NF molecule are found by using highly accurate multireference configuration interaction plus the Davidson correction with the AV5Z basis set. All 16 electrons are used in the correlation energy calculations, which are used to characterize the spectroscopic properties of a manifold for singlet and triplet states. [X.sup.3][∑.sup.-], [a.sup.1]Δ, [b.sup.1][∑.sup.1], [A.sup.3]Π, 2[3.sup.2]Π, [2.sup.3]Π, [2.sup.1]Δ, [3.sup.3][∑.sup.-], [1.sup.3]∑.sup.+], and [1.sup.3]Δ electronic states correlate with the two lowest dissociation channels N([sup.4][S.sub.u]) + F(²[P.sub.u]) and N(²[D.sub.u]) + F(²[P.sub.u]) are investigated. Note that the [b.sup.1][∑.sup.+] state has two depth wells, but only one depth well was observed in the experiment. The spectroscopic parameters ([R.sub.e], [ω.sub.e], [ω.sub.e][χ.sub.e], [D.sub.e], [B.sub.e], and [T.sub.e]) are derived, which are in excellent agreement with the available experimental data and the other theoretical values. The molecular parameters and dipole moments for the ground and excited states are also obtained. Key words: inner electron correlation, potential energy curves, spectroscopic parameters, molecular parameters, dipole moment. Nous utilisons la methode precise d'interaction de configuration multi-reference plus les corrections de Davidson avec l'ensemble de base AV5Z, afin de calculer les courbes d'energie potentielle et les moments dipolaires des etats electroniques de basse energie de la molecule de NF. Les 16 electrons sont conserves dans les calculs d'energie de correlation, qui sont utilises pour caracteriser les proprietes spectroscopiques des etats de type singlet et triplet. Nous analysons la correlation des etats electroniques [X.sup.3][∑.sup.-], [a.sup.1]Δ, [b.sup.1] [∑.sup.+], [A.sup.3]Π, [2.sup.3][∑.sup.-], [2.sup.3]Π, [2.sup.1]Δ, [3.sup.3][∑.sup.-], [1.sup.3][∑.sup.+] et [1.sup.3]Δ, avec deux canaux inferieurs de dissociation N([sup.4][S.sub.u]) + F(²[D.sub.u]) et N(²[D.sub.u]) + F(²[P.sub.u]). Notez que l'etat [b.sup.1]n[[product].sup.+] possede deux profondeurs de puits, une seule etant observee experimentalement. Nous obtenons les parametres spectroscopiques ([R.sub.e], [ω.sub.e], [ω.sub.e], [χ.sub.e], [D.sub.e], [B.sub.e], [T.sub.e]), et ils sont en excellent accord avec les donnees experimentales disponibles et d'autres valeurs theoriques. Nous obtenons egalement les parametres moleculaires et les moments dipolaires pour le fondamental et les etats excites etudies. [Traduit par la Redaction] Mots-cles : correlations entre electrons des couches internes, courbes d'energie potentielle, parametres spectrometriques, parametres moleculaires, moment dipolaire. PACS Nos.: 31.10.+z, 31.15.A-, 31.15.vn, 31.50.Df., 1. Introduction The NF molecule was always considered an intermediate in some chemical reactions, such as the H + N[F.sub.2] reaction [1-3], N + N[F.sub.2] and H + NF reaction [...]

Electric dipole oscillator strengths and lifetimes for Cu I have been calculated within the weakest bound electron potential model theory and the quantum defect orbital theory under the assumption of the LS coupling scheme. In the calculations, many transition arrays including both multiplet and fine-structure transitions are considered. The present results are consistent with earlier theoretical calculations and experimental measurements. Some of these results are reported for the first time. PACS No.: 32.70.Cs. Nous utilisons le modele du potentiel de l'electron le plus faiblement lie et L[alpha] theorie de l'orbitale a defaut quantique dans un schema de couplage LS, afin de calculer les forces d'oscillateur dipolaires et les temps de vie du Cu I. Ces calculs tiennent compte de plusieurs sequences transitionnelles, incluant de multiplet et de structure fine. Nos resultats sont coherents avec des calculs theoriques anterieurs et avec des mesures experimentales. Certains resultats presentes ici sont inedits. [Traduit par L[alpha] Redaction], 1. Introduction Looking at the ground level configuration of Cu I, there exists one electron other than the closed electrons. Neutral copper is similar to an alkali atom. Atomic structure [...]

A compact circularly polarized (CP) vertical patch antenna is presented that employs a microstrip to slot-line transition for a wideband operation. The antenna is composed of two vertical patches, which are shaped as helix to obtain a broadband CP performance. The loop structure and the vertical overlap configuration lead to significant size reduction as much as 48% when compared to that of the printed dual-loop antenna. Simulated results agree well with the measurement, showing that the antenna possesses a wide axial ratio (AR < 3 dB) bandwidth of 28.5%, and a broad return loss ([S.sub.11] < -10 dB) bandwidth of 37.8%. Also, it has symmetric radiation patterns and low cross-polarization levels in the broadside direction over the operating bandwidth. Moreover, the antenna gain is around 8 dBi, and it is very stable across the operating bandwidth. Index Terms--Broadband antennas, circularly polarized antennas, vertical patch antennas.

A method of preventing the degradation in the isolation between the orthogonal polarization ports caused by beamforming network routing in combined edge/aperture fed dual-polarized microstrip-patch planar array antennas is described. The simulated and measured performance of such planar arrays is demonstrated. Measured port isolations of 50 dB at center frequency, and more than 40 dB over a 4% bandwidth, are achieved. In addition, insight into the physical reasons for the improved port-to-port isolation levels, of the proposed element geometry and beamforming network layout, is obtained through prudent use of the electromagnetic modelling. Index Terms--Dual-polarized array, port isolation.

A novel type of short monopole antenna is proposed. Its structure consists of a periodically slotted coaxial line radiating in linear polarization (LP). The structure can be easily modified by the addition of a thin layer of dipoles in order to generate circular polarization (CP). The number of slots along the structure, their periodicity and the tuning of the terminating load allow control of the antenna main beam' angle and width. One advantage of the proposed design over conventional monopoles is that the antenna does not require a ground plane. Both left-hand and right-hand CP are possible with the same design, simply by inverting the symmetry of the printed dipoles. Design details for the annular slotted coaxial line and for the LP and CP mast antennas are given. Prototypes in both LP and CP were fabricated and their characteristics were measured. Simulations and measurement are in good agreement. The proposed CP mast antenna is compliant with the requirements of the XM digital satellite radio system, with a frequency bandwidth of more than 1.7% in which VSWR < 2, and an AR < 4 dB in the elevation range of [+ or -]30[degrees] < [theta] < [+ or -]70[degrees]. Index Terms--Coaxial transmission line discontinuities, mobile antenna, monopole antenna, printed dipoles, slot arrays.

The insulation research and development programs carried out during the first phase of the Next European Dipole (NED) project are described. The role of sizing on glass fiber insulation subjected to [Nb.sub.3]Sn magnet processing parameters is studied by using thermo gravimetric analysis.

The dipole moment in the space anti-matter detector AMS01 magnet is analyzed and a compensating method is developed for the dipole moment in AMS01. The analysis has shown that the reasonable installing position of permanent magnet blocks have reduced the affect to the central magnetic induction in AMS01.

The dipole design study with flat horizontal poles that allow a low variation of the vertical tune is described. It is shown that distributed conductors require intense examinations to produce a non-linear field law in full 3d geometry, because a high current intensity has concentrated the flux in small region of the pole.

The organization implemented at CERN and the milestones fixed to fulfill the technical requirements and to respect the master schedule of the machine installation are described. The production of the main dipole cold masses for LHC has necessitated the participation of a great number of people at CERN.

The preparatory work ongoing at CRPP to integrate the EFDA dipole (EDIPO) test facility is discussed. The preparatory work has included the design and procurement of many items as well as the final assembly and commissioning of the facility.

Two planar coil windings are studied in order to produce a required level of vertical field inside a rectangular shaped bore. Their performances are compared with the reference the EFDA dipole (EDIPO) configuration, which is based on different cost indexes and different winding engineering current densities.

A new joint design is developed and patented by ENEA in the framework of the EFDA dipole (EDIPO) activities. The analysis has shown a resistance < 0.5 n[omega], while the first trial of adapting it to the EDIPO realization needs have given a value 10 times higher.

The LHC cold mass manufacturing is a challenging project that has required a strong effort in terms of engineering and man power to assess the required high quality level. The production of LHC dipoles in ASG Superconductors is completed almost on time, thus keeping the average losses well below 5%

The rotational spectra five isotopic species of the weakly bound complex between methyl fluoride and carbonyl sulfide are measured. Closely related species of methyl fluoride are found by calculating dipole moments and rotational constants of these species.

The triplet state of dipole moments of aminobenzonitriles is recalculated on the basis of newly measured intersystem crossing yields. The dipole moment of 4-(dimethylamino)benzonitrile (DMABN) in the triplet state is not found to be a reliable indication of the extent of charge transfer compared to other states.

The construction of molecular-scale lipid model and use of molecular dynamic simulation to analyze the role of head group dipoles in the formation of the ripple phase is described. The model is able to achieve an out-of-plane membrane corrugation that stabilizes the orientational ordering for the dipoles in the head groups which develop an anti-ferroelectric state.

The structures, C-H stretching frequencies and dipole moments of the HCN-[Ag.sub.n] (n=1-4) complexes formed in superfluid helium droplets were determined by high-resolution infrared spectroscopy. All monoligated species are bound through the nitrogen end of the HCN molecule and the interaction between the HCN and the [Ag.sub.n] clusters are slightly weaker because of the more diffuse nature of electrons surrounding the silver atom.

The magnetic and thermal characteristics of a 1m model dipole with optimized 3D and 2 D geometries are presented. Findings reveal the critical temperature of the dipole to be 5.69 K, the operating temperature to be 4.79 K, while the temperature margin is 0.9 K.

In most experimental searches for the electron electric dipole moment, one searches for a linear Stark effect in a paramagnetic atom or molecule and interprets the result in terms of the electric dipole moment of the unpaired valence electron(s). Schiff's theorem states that in the limit of nonrelativistic quantum mechanics, there can be no linear Stark effect to first order in the electric dipole moment. Sandars has shown that Schiff's theorem is not applicable when special relativity is taken into account. We give a heuristic explanation for this relativistic effect, which corrects a widespread misconception in the literature. [DOI: 10.1119/1.2710486]

The Schrrdinger equation for a point charge in the field of a stationary electric dipole admits bound states only when the dipole moment exceeds a certain critical value. It is not hard to see why this might be the case, but it is surprisingly difficult to calculate the critical dipole moment. The analogous problem should be simpler in one and two dimensions, but a general theorem forbids critical moments in one dimension, and explicit calculation shows that there is no critical moment in two dimensions. [DOI: 10.1119/1.2710485]

The spectroscopic properties for the intermanifold and inter-stark transitions of trivalent neodymium [Nd.sup.3}(4[f.sup.3]) doped polycrystalline ceramic yttria, [Y.sub.2][O.sub.3] are studied. The results show that in spite of the presence of magnetic dipole transitions, the electric dipole transitions are dominant in such structures and hence lead to a more economical fabrication.

The detailed mechanisms for amplifying contrast due to small spatial variations in magnetic resonance (MR) parameters through the individual and joint feedback fields of the distant dipolar field and radiation damping are proposed. The understanding of such mechanisms presents insight into the use of such feedback fields in current MR imaging and MR microscopy experiments and inspires the future design of pulse sequences that might ultimately grant the user control in tuning the contrast amplification factor, thereby surmounting specific experimental constraints.

The effect of partial monolayers of molecular dipoles at semiconductor/metal interfaces on the electrical transport across these interfaces is examined by using a series of molecules with systematically varying dipole moment. The results have shown that molecules can control and tailor electronic devices need not form high-quality monolayers, bind chemically to both electrodes, and form multilayers to achieve complete surface coverage.

A novel approach is developed to simultaneously achieve high first-order hyperpolarizability [beta] values while providing an adjustable dipole moment by linking a strong neutral-ground-state (NGS) nonlinear optical (NLO) chromophore with positive [beta] to a zwitterionic (ZWI) chromophore with negative [beta] in an antiparallel fashion. The results have shown that an antiparallel-aligned NGS chromophore and a zwitterionic chromophore can simultaneously achieve an increase in [beta] and a decrease of the dipole moment.

The structures of heterogeneous proton-bound dimers containing monomers such as acetonitrile, cyanamide, vinylene carbonate and propiolactone having high dipole moments are explored. A simple model based on the interplay between electrostatic and covalent bonding of the proton is presented and is tested on various proton-bound dimers.

The Extended Couple Dipole Model (ECDM) is a trilinear component model that can be used to analyze multiple, related magneto-encephalogram (MEG) data sets simultaneously. Related MEG data sets are those that contain activity of the same sources or activity of sources that have proportional source amplitudes.

The design, fabrication and measurement of a volumetric metamaterial realization of an artificial magnetic conductor (AMC) is presented. In contrast to most current realizations of AMCs, such as the mushroom and the uniplanar compact photonic bandgap surfaces, the present design has no perfect electric conductor ground plane. The perfect magnetic conductor properties were designed with capacitively loaded loops for X band operation at 10 GHz. Very good agreement between the numerical and experimental scattering results was achieved. The performance of a dipole antenna radiating in the presence of this volumetric metamaterial AMC is quantified numerically. Resonant interactions of the antenna and metamaterial structure lead to a significant enhancement of the radiated field amplitudes and isolation measured as the front-to-back ratio. Index Terms--Antennas, artificial dielectrics, artificial magnetic conductor (AMC), metamaterials, scattering.

The electrostatic dipole moment distribution in heterogeneous suspensions is determined through a self-consistent, point-dipole model, which incorporated nonlocal electrostatics. For small fluctuations are concentration, the dipole strength can be expressed as an expansion in gradients of the concentration.

Binary mixtures of 1-methyl pyrrolidin-2-one (NMP) with alkanes, benzene, toluene, 1-alkanol, or 1-alkyne have been investigated in the framework of the DISQUAC model. The reported interaction parameters change regularly with the molecular structure of the mixture components. The model consistently describes a set of thermodynamic properties, including liquid-liquid equilibria, vapor liquid equilibria, solid-liquid equilibria, and molar excess enthalpies. A brief comparison of the DISQUAC results and those obtained from the UNIFAC and ERAS models is presented. The experimental excess enthalpies are better represented by DISQUAC than by UNIFAC because this quantity strongly depends on molecular structure. For NMP + alkane mixtures, the liquid-liquid equilibria data are also better represented by DISQUAC, while UNIFAC more accurately describes the vapor-liquid equilibria measurements at temperatures close to the critical point. This result suggests that a mean field theory is not able to represent simultaneously, with the same set of interaction parameters, liquid-liquid and vapor-liquid equilibria at the mentioned temperatures. ERAS fails when treating mixtures with 1-alkanols. This has been attributed to the strong dipole-dipole interactions between NMP molecules, characteristic of the investigated systems. Mixture structure is briefly studied in terms of the concentration--concentration structure factor. Key words: thermodynamics, NMP, organic solvent, self-association, dipole-dipole interactions.

While radio frequency (RF) catheter ablation (RCA) procedures for treating ventricular arrhythmias have evolved significantly over the past several years, the use of RCA has been limited to treating slow ventricular tachycardias (VTs). In this paper, we present preliminary results from computer and animal studies to evaluate the accuracy of an algorithm that uses the single equivalent moving dipole (SEMD) model in an infinite homogeneous volume conductor to guide the RF catheter to the site of origin of the arrhythmia. Our method involves measuring body surface electrocardiographic (ECG) signals generated by arrhythmic activity and by bipolar current pulses emanating from a catheter tip, and representing each of them by a SEMD model source at each instant of the cardiac cycle, thus enabling rapid repositioning of the catheter tip requiring only a few cycles of the arrhythmia. We found that the SEMD model accurately reproduced body surface ECG signals with a correlation coefficients >0.95. We used a variety of methods to estimate the uncertainty of the SEMD parameters due to measurement noise and found that at the time when the arrhythmia is mostly localized during the cardiac cycle, the estimates of the uncertainty of the spatial SEMD parameters (from ECG signals) are between 1 and 3 mm. We used pacing data from spatially separated epicardial sites in a swine model as surrogates for focal ventricular arrhythmic sources and found that the spatial SEMD estimates of the two pacing sites agreed with both their physical separation and orientation with respect to each other. In conclusion, our algorithm to estimate the SEMD parameters from body surface ECG can potentially be a useful method for rapidly positioning the catheter tip to the arrhythmic focus during an RCA procedure. Index Terms--Catheter ablation, equivalent moving dipole, arrhythmias.

1,3-dipolar cycloaddition of nitrones to nitriles - free and ligated to Pt(super II) and Pt(super IV) in the platinum complexes - is investigated by theoretical methods at different levels of theory, and the substituent and solvent effects are studied. The calculations show that the cycloaddition of nitrones to nitriles is mainly determined by the HOMO(sub nitrone-) LUMO(sub nitrile) type of interaction even for the acetonitrile with the electron-donor methyl group.

The van der Waals induced moment is derived using a reaction field approach based on charge density susceptibilities of several bodies interacting through Coulomb operators. The work function reductions of magnesium by argon and xenon can be accounted for by the calculations.

The solvation of ions in diplor lattice droplets is studied using Monte Carlo simulations. It is found that for small dipoles the solvation behavior is similar to that expected from a dielectric model.

The operation of the exponential of the curl on a general vector field is studied. It is nonlocal, and it is shown that the resultant field may be written as the sum of integrals over all space. The formal solutions of the time-dependent Maxwell's equations for an arbitrary current density are first written in terms of the curl, and explicit expressions for the electric and magnetic fields are given in terms of the source current densities loaded with these kernels. This method of deriving the fields obviates the introduction of electromagnetic potentials. The well-known expressions for the fields are derived for a fixed oscillating dipole and a charge in arbitrary motion. For a moving dipole the source current includes, in addition to the polarization current, a coupling of the polarization to the velocity of the dipole known as the Rontgen current. The magnetic field due to this current is given.