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Our lattice simulation accounts for the significant inhibition of lithium-dendrite growth in ionic liquids. We also show that our ensemble neural networks can further capture this simulation, which significantly reduces statistical sampling in the lattice simulation.

We provide a perspective on the thermodynamics of salt-doped block copolymer electrolytes consisting of ion-conducting and inert blocks, taking poly(ethylene oxide)-b-polystyrene and lithium salts as an example. We focus on the origin for enhanced immiscibility between the constituent blocks upon addition of lithium salts and discuss issues from selected experiments and from our recent self-consistent field study.

We calculate the solvation energy of monovalent and divalent ions in various liquids with coarse-grained molecular dynamics simulations. Our theory treats the solvent as a Stockmayer fluid, which accounts for the intrinsic dipole moment of molecules and the rotational dynamics of the dipoles. Despite the simplicity of the model, we obtain qualitative agreement between the simulations and experimental data for the free energy and enthalpy of ion solvation, which indicates that the primary contribution to the solvation energy arises mainly from the first and possibly second solvation shells near the ions. Our results suggest that a Stockmayer fluid can serve as a reference model that enables direct comparison between theory and experiment and may be invoked to scale up electrostatic interactions from the atomic to the molecular length scale.

We study the phase behavior of a block copolymer and ionic liquid mixture using the Landau theory of Leibler and field-theoretic techniques in polymer physics. Our weak-segregation theory of microp...

In fashion electronic commerce services, two item-based recommendation approaches, image similarity-based and click likelihood-based, are used to improve the revenue of a website. To improve accuracy, in this paper, we propose a hybrid model, a deep neural network (DNN) that predicts click probability of a target fashion item by incorporating both image similarity and click likelihood. To create an image similarity feature, we acquire a latent image feature through a CNN-based classification of fashion color, type and pattern. To create a click likelihood feature, we calculate matrix factorization (MF) and use decomposed item features as latent click log feature. To solve a cold-start problem (recommendation of new items), we complement the latent log features of new items with those of existing ones. An offline evaluation shows that the accuracy of proposed model (both log and image) improved by 14% compared with matrix factorization (log only) and 56% the image-only model. Moreover, the complement of latent log features changes the new item ratio to six times.

Water dissolved in ionic liquids garners particular attention in electrochemistry, as represented by the case where water molecules cannot be completely removed from ionic liquids. Nevertheless, the effects of such polarizable polar molecules on the energy efficiency of electrochemical devices remain elusive. Thus, we highlight the effects of the spatially varying dielectric response of water and ionic liquid near charged plates using a coarse-grained mean-field theory that simultaneously accounts for both the permanent and induced dipole moments of the species and the strong electrostatic correlation. We show that water can be adsorbed onto electrodes primarily because of the dielectric contrast between the species. Our results predict that linear-dielectric theory is inadequate to account for the correlation between the capacitance and dielectric contrast, which may be fitted by exponential functions. Electronic polarizability can enhance the capacitance. A higher-dielectric component preferentially solvates electrodes, but this effect competes with that of the charge screening. Our theory shows that strong electrostatic correlation causes the dipolar cation and anion to form alternating layers, which in turn yields substantial increases in the capacitance. Our results compare favorably with previous molecular dynamics simulations.

We illustrate the effects of chain connectivity on the solvation energy of ions immersed in polymer liquids by developing a new coarse-grained molecular dynamics simulation. Our theory accounts for the dielectric response of the polymers through the connection of dipolar, monomeric units with nonlinear springs. In stark contrast to the standard Born solvation energy of ions, our results depend substantially on the chain length of the polymers. We also demonstrate the marked difference in the solvation energies of the ions immersed in non-polymeric particle mixtures, single-component polymers, polymer blends, and block copolymers. Thus, we suggest that the chain architecture of polymers is a key factor in ion solvation, whereas this feature is often inadequately considered in main theory and simulation literature. Our results are consistent with those predicted by previous coarse-grained mean-field theories when the dipole moment of the polymer compositions is relatively small. However, we also demonstrate that the strong ion-dipole and dipole-dipole interactions cause the chain-like association of the monomeric units, resulting in a qualitative discrepancy between the mean-field theory and simulation. Such a strong electrostatic correlation may reverse the dependence of the chain length on the solvation energy of the ions in the polymers.

We studied the spinodal decomposition of a homopolymer and ionic liquid mixture. Our theory accounts for the dielectric contrast and hydrogen bond between the polymer and the ionic liquid and the effect of fluctuations in the local density and electrostatic potential. We attempted to rationalize the observed shift in the critical point and the asymmetry of the observed spinodal curve by applying the self-consistent field theory and Langmuir adsorption model. The dielectric contrast between the polymer and the ionic liquid produces a shift in the critical point toward polymer-rich regions. The fluctuation effect yields drastic changes in the trend of the phase boundary. We show that both effects are marked by the appearance of inflection points in the spinodal curve. Although hydrogen bonding also yields similar effects, the spinodal curve rather exhibits a double-well structure or relatively flat structure when combined with the solvation energy of ions. Hydrogen bonding, ion solvation, and the fluctuatio...

Taking PEO/PS polymer blends doped with lithium salt as example, we study the effects of cross-linking of the EO segments by the Li+ ions on the phase behavior. Combining the Flory–Huggins theory with a statistical model accounting for the combinatorics in forming the cross-links and accounting for the charge neutrality due to the presence of anions, we find an entropic driving force that favors phase separation when the number of EO segments coordinating an Li+ ion exceeds 2. As a result of the asymmetric interaction between the ions and the two polymers, the phase diagram in the polymer composition becomes asymmetric upon addition of the lithium salts. In addition, we examine the effects of preferential solvation energy of the ions which has been shown previously to lead to an increase in the effective χ parameter between the two polymers. We find that the magnitudes of these two driving forces are comparable, but their effects are nonadditive.

We study the dielectric properties of single-component liquids and liquid mixtures between charged plates and develop a modified Poisson–Boltzmann (PB) equation using Booth’s theory. Our theory accounts for the permanent dipole moment and polarizability of solvents and the hydrogen bonds between solvents. We demonstrate that these key parameters are crucial for capturing the reorientation of solvent dipoles under external electrostatic fields. Our results show that variations in the capacitance of ionic solutions can be nonmonotonic, whereas the conventional PB theory predicts monotonic behavior. Specifically, the effect of hydrogen bonding produces highly nonmonotonic behavior that depends on the surface charge density and applied voltage. The resultant capacitance can be enhanced by hydrogen bonding, but a significant decline in the capacitance can also occur as the applied voltage is increased. Furthermore, our novel finding is that field-induced changes in the dielectric value may cause the unconventi...

We studied ionic liquids confined between charged plates to develop a dipolar self-consistent field theory (DSCFT) for incompressible states and a hybrid of DSCFT combined with Monte Carlo simulation for compressible states. Our theory, which has no adjustable parameters, accounts for the differences between the dipole moments and the molecular volumes of the cation and anion, the hard-core nature of the ions, and the electrical double layer formed through the strong association of the ions with the electrodes. We illustrate that a spatial change in the distributions of cations and anions with different dipole moments causes a significant spatial change in the dielectric function and hence gives rise to spatial asymmetry in the electrostatic field between the charged plates. Notably, this effect can be comparable to that caused by an asymmetry in the molecular volumes of the cation and anion. Moreover, the hard-core nature of ionic liquids causes oscillations in the density profile near the charged plates. We also demonstrate that a contrast in the dielectric values of the cations and anions in ionic liquids causes a substantial decrease in capacitance as the applied voltage is increased. The magnitude of this variation can be noticeably altered by changing the dipole moments of the cation and anion.

Block copolymer/lithium salt mixtures are promising materials for lithium battery electrolytes. The growth of ordered lamellar grains after a block copolymer electrolyte was quenched from the disordered state to the ordered state was studied by depolarized light scattering. Three quench depths below the order-to-disorder transition temperature were studied: 6, 12, and 24 °C. Regardless of quench depth, elongated ellipsoidal grains with aspect ratios between six and eight were formed during the initial stage of order formation. This was followed by a rapid reduction in aspect ratio; at long times, isotropic grains with aspect ratios in the vicinity of unity were obtained. Unusual grain growth kinetics were observed at all quench depths: (1) The average grain volume decreased with time after the early stage of grain growth. To our knowledge, a decrease in grain size has never been observed before in any quenched block copolymer system. (2) The volume fraction occupied by ordered grains of the shallowest que...

We studied the thermodynamic properties of ion solvation in polymer blends and block copolymer melts and developed a dipolar self-consistent field theory for polymer mixtures. Our theory accounts for the chain connectivity of polymerized monomers, the compressibility of the liquid mixtures under electrostriction, the permanent and induced dipole moments of monomers, and the resultant dielectric contrast among species. In our coarse-grained model, dipoles are attached to the monomers and allowed to rotate freely in response to electrostatic fields. We demonstrate that a strong electrostatic field near an ion reorganizes dipolar monomers, resulting in nonmonotonic changes in the volume fraction profile and the dielectric function of the polymers with respect to those of simple liquid mixtures. For the parameter sets used, the spatial variations near an ion can be in the range of 1 nm or larger, producing significant differences in the solvation energy among simple liquid mixtures, polymer blends, and block copolymers. The solvation energy of an ion depends substantially on the chain length in block copolymers; thus, our theory predicts the preferential solvation of ions arising from differences in chain length.

Surface deformations were induced in azo-polymer films by a focused laser spot that has a longitudinal field (Ez). We found that the deformation patterns induced by Ez were strongly dependent on polymer film thickness. The polymer formed a dip at the center of the focused spot when the film thickness is thinner than 37 nm, while the polymer formed a protrusion when the film thickness is thicker than 37 nm. These results imply that upward and downward forces are competing inside the polymer film, and the balance between them finally decides the surface topology (dip versus protrusion) of the film. We also found that the deformation patterns were dependent on the refractive index of the material on the film. We calculated the light field distribution inside the polymer film, and by comparing the experimental results we found that both anisotropic photofluidic force and optical gradient force might play important roles in the polymer movement. In addition, we found by changing the wavelength of the irradiati...

We study the solvation of ion pairs in diblock copolymer melts. Our theory accounts for the size of the ions, the permanent dipole moment and the molecular polarizability of the monomers, the Kuhn length, the compressibility of the liquid mixtures, and the degrees of polymerization. We demonstrate that the electrostatic field near an ion pair causes marked, synergistic effects on the volume fractions of the two blocks and hence the dielectric function. In particular, we illustrate the oscillatory behavior of the dielectric function near an ion pair and the disparity of the dielectric functions between like and unlike charges. These results depend significantly on the chain length and Kuhn length of the diblock copolymers on the nanometer scale.

Polymer-polymer complexation in solvent is studied using an extension of the self-consistent field theory. The model polymers are capable of forming ladder-like duplex structures. The duplex formation occurs with an abrupt change of entropy, resulting in a first-order transition. Moreover, the complexation can be stabilized by solvent-polymer interactions, instead of the usual specific binding interactions. Various types of unconventional phase diagrams are predicted. For example, phase separation with decreasing χ-parameter between duplex polymer and solvent can be induced, leading to a lower critical solution temperature (LCST) behavior. Multiphase coexistence points at which two, three, or four phases coexist are also obtained. Under certain conditions a homogeneous phase becomes unstable when the polymer chain length is decreased, in contrast to the standard Flory-Huggins theory.

The human skin microbiome can vary over time, and inter-individual variability of the microbiome is greater than the temporal variability within an individual. The skin microbiome has become a useful tool to identify individuals, and one type of personal identification using the skin microbiome has been reported in a community of less than 20 individuals. However, identification of individuals based on the skin microbiome has shown low accuracy in communities larger than 80 individuals. Here, we developed a new approach for personal identification, which considers that minor taxa are one of the important factors for distinguishing between individuals. We originally established a human skin microbiome for 66 samples from 11 individuals over two years (33 samples each year). Our method could classify individuals with 85% accuracy beyond a one-year sampling period. Moreover, we applied our method to 837 publicly available skin microbiome samples from 89 individuals and succeeded in identifying individuals with 78% accuracy. In short, our results investigate that (i) our new personal identification method worked well with two different communities (our data: 11 individuals; public data: 89 individuals) using the skin microbiome, (ii) defining the personal skin microbiome requires samples from several time points, (iii) inclusion of minor skin taxa strongly contributes to the effectiveness of personal identification.

We develop a new, rapid method for the lattice Monte Carlo simulation of ion-containing liquids that accounts for the effects of the reorganization of solvent dipoles under external electrostatic fields. Our results are in reasonable agreement with the analytical solutions to the dielectric continuum theory of Booth for single ions, ion pairs, and ionic cross-links. We also illustrate the substantial disparity between the dielectric functions for like and unlike charges on the nanometer scale. Our simulation rationalizes the experimental data for the dependence of the bulk dielectric value of water on ion concentrations in terms of saturated dipoles near ions.

We investigate the dose and dose-rate dependence of the mutation frequency caused by artificial radiations with Whack-A-Mole (WAM) model which we have recently proposed. In particular, we pay special attention to the case of long-term and low dose-rate exposure. The results indicate that the dose-rate dependence is successfully described with WAM model and it may replace the so-called DDREF, the concept of which has long been adopted to take account of the difference between the high dose-rate data and the low dose-rate ones. Basic properties of WAM model are discussed emphasizing the dose-rate dependence to demonstrate how the explicit dose-rate dependence built in the model plays a key role. By adopting the parameters that are determined to fit the mega mouse experiments, biological effects of long-term exposure to extremely low dose-rate radiation are discussed. In WAM model, the effects of the long-term exposure show a saturation property, which makes a clear distinction from the LNT hypothesis which predicts a linear increase of the effects with time., 20 pages, 5 figures, 2 tables, submitted to Journal of Nuclear Science and Technology

We present a novel model to estimate biological effects caused by artificial radiation exposure, Whack-a-mole (WAM) model. It is important to take account of the recovery effects during the time course of the cellular reactions. The inclusion of the dose-rate dependence is essential in the risk estimation of low dose radiation, while nearly all the existing theoretical models relies on the total dose dependence only. By analyzing the experimental data of the relation between the radiation dose and the induced mutation frequency of 5 organisms, mouse, drosophila, chrysanthemum, maize and tradescantia, we found that all the data can be reproduced by WAM model. Most remarkably, a scaling function, which is derived from WAM model, consistently accounts for the observed mutation frequencies of 5 organisms. This is the first rationale to account for the dose rate dependence as well as to give a unified understanding of a general feature of organisms., 26 pages, 4 figures, 1 table, Journal of the Physical Society of Japan accepted

Mixtures of block copolymers and lithium salts are promising candidates for lithium battery electrolytes. Structural changes that occur during the order-to-disorder transition (ODT) in a diblock copolymer/salt mixture were characterized by small-angle X-ray scattering (SAXS). In salt-free block copolymers, the ODT is sharp, and the domain size of the ordered phase decreases with increasing temperature. In contrast, the ODT of the diblock copolymer/salt mixture examined here occurs gradually over an 11 °C temperature window, and the domain size of the ordered phase is a nonmonotonic function of temperature. We present an approach to estimate the fraction of the ordered phase in the 11 °C window where ordered and disordered phases coexist. The domain spacing of the ordered phase increases with increasing temperature in the coexistence window. Both findings are consistent with the selective partitioning of salt into the ordered domains, as predicted by Nakamura et al. (ACS Macro Lett. 2013, 2, 478-481). © 2014 American Chemical Society.

We develop a kinetic reaction model for cells having irradiated DNA molecules due to ionizing radiation exposure. Our theory simultaneously accounts for the time-dependent reactions of the DNA damage, the DNA mutation, the DNA repair, and the proliferation and apoptosis of cells in a tissue with a minimal set of model parameters. In contrast to existing theories for radiation exposition, we do not assume the relationships between the total dose and the induced mutation frequency. Our theory provides a universal scaling function that reasonably explains the mega-mouse experiments in Ref.[W. L. Russell and E. M. Kelly, Proc. Natl. Acad. Sci. USA. {\bf 79} (1982) 542.] with different dose rates. Furthermore, we have estimated the effective dose rate, which is biologically equivalent to the ionizing effects other than those caused by artificial irradiation. This value is $ 1.11 \times 10^{-3} ~\rm{[Gy/hr]}$, which is significantly larger than the effect caused by natural background radiation., Comment: 12 pages, 3 figures

We illustrate the effects of dielectric inhomogeneity on the statistical properties of polyelectrolytes in solution, by a lattice Monte Carlo simulation that combines the bond fluctuation model with a local algorithm for computing the electrostatic interactions. Our model accounts for the difference in the dielectric properties between the polymer backbone and the solvent. Taking the coil–globule transition of a single polyelectrolyte chain in solvent as an example, we show that the chain conformation and the degree of counterion condensation are substantially affected by the dielectric contrast.

Using field-theoretic techniques, we study the solvation of salt ions in liquid mixtures, accounting for the permanent and induced dipole moments, as well as the molecular volume of the species. With no adjustable parameters, we predict solvation energies in both single-component liquids and binary liquid mixtures that are in excellent agreement with experimental data. Our study shows that the solvation energy of an ion is largely determined by the local response of the permanent and induced dipoles, as well as the local solvent composition in the case of mixtures, and does not simply correlate with the bulk dielectric constant. In particular, we show that, in a binary mixture, it is possible for the component with the lower bulk dielectric constant but larger molecular polarizability to be enriched near the ion.

We apply a self-consistent relativistic mean-field variational “Gaussian functional” (or optimized one-loop perturbation theory, or Hartree+RPA) approximation to the extended N_f=2 linear σ model with spontaneously and explicitly broken chiral SU_R(2)×SU_L(2)×U_A(1)≡O(4)×O(2) symmetry. We set up the self-consistency, or gap equations that dress up the bare fields with “cactus tree” loop diagrams, and the Bethe-Salpeter equations that provide further dressing with one-loop irreducible diagrams. In a previous publication [ V. Dmitrasinovic and I. Nakamura J. Math. Phys. (N.Y.) 44 2839 (2003)] we have already shown the ability of this approximation to create composite (i.e., bound and/or resonance) states. With explicit SU_R(2)×SU_L(2)×U_A(1) chiral symmetry breaking first we consider how the U_A(1) symmetry induced scalar-pseudoscalar meson mass relation that is known to hold in fermionic chiral models is modified by the bosonic gap equations. Then we solve the gap and Bethe-Salpeter equations numerically and discuss the solutions’ properties and the particle content of the theory. We show that in the strong-coupling regime two, sometimes even three solutions to the η meson channel Bethe-Salpeter equation may coexist.

We develop a theory for the thermodynamics of ion-containing polymer blends and diblock copolymers, taking polyethylene oxide (PEO), polystyrene and lithium salts as an example. We account for the tight binding of Li^{+} ions to the PEO, the preferential solvation energy of anions in the PEO domain, the translational entropy of anions, and the ion-pair equilibrium between EO-complexed Li^{+} and anion. Our theory is able to predict many features observed in experiments, particularly the systematic dependence in the effective χ parameter on the size of the anions. Furthermore, comparison with the observed linear dependence in the effective χ on salt concentration yields an upper limit for the binding constant of the ion pair.

A self-consistent field theory is developed for polymers that are capable of binding small ionic molecules (adsorbates). The polymer-ionic molecule association is described by Ising-like binding variables, C(i) ((a))(kDelta)(=0 or 1), whose average determines the number of adsorbed molecules, n(BI). Polymer gelation can occur through polymer-ionic molecule complexation in our model. For polymer-polymer cross-links through the ionic molecules, three types of solutions for n(BI) are obtained, depending on the equilibrium constant of single-ion binding. Spinodal lines calculated from the mean-field free energy exhibit closed-loop regions where the homogeneous phase becomes unstable. This phase instability is driven by the excluded-volume interaction due to the single occupancy of ion-binding sites on the polymers. Moreover, sol-gel transitions are examined using a critical degree of conversion. A gel phase is induced when the concentration of adsorbates is increased. At a higher concentration of the adsorbates, however, a re-entrance from a gel phase into a sol phase arises from the correlation between unoccupied and occupied ion-binding sites. The theory is applied to a model system, poly(vinyl alcohol) and borate ion in aqueous solution with sodium chloride. Good agreement between theory and experiment is obtained.

Three-dimensional molecular orientations of single fluorescence molecules in polymeric thin films were measured by focused azimuthally and radially polarized light, in which we found that the fluorescence intensity was dependent on the depth position of the molecule with respect to the film surface. We found that the fluorescence intensity for a molecule which is 80 nm deep in the film excited by radial polarization is appreciably larger when compared with the fluorescence intensity for a molecule which is also excited by radial polarization but which is closer to the polymer/air interface, a feature which leads to different fluorescence intensities, under excitation by radial polarization, for molecules with the same polar orientation but with different depths inside the film. We also found that the variation of fluorescence intensity from a molecule inside an 80 nm film in radial polarization is appreciably larger compared with one in azimuthal polarization. These findings were confirmed by comparing experiments using different thickness films with theoretically calculated electric field distributions.

A simple model composed of two rigid macromolecules (adsorbents) immersed in a large number of small molecules (adsorbates) is used to study entropy-driven association processes. The surfaces of the adsorbents are capable of adsorbing the smaller adsorbates. The partition function of the model is obtained analytically. The probability of dimerization and the number of adsorbed molecules are shown to depend on the enthalpy and the entropy differences between the assembled and the disassembled states. Under certain conditions, dimerization of the macromolecules occurs with increasing temperature. This entropy-driven self-assembly is originated from an overall entropy gain due to the release of the adsorbed small molecules, leading to a large peak in the heat capacity due to the dimer formation. The desorption of the adsorbates induces a sharp change in the first-order derivative of the free energy, resulting in another large peak in the heat capacity. A temperature-induced re-entrance into the dimer state is also contained in the model.

DNA aptamers are molecular biosensors consisting of single functionalized DNA molecules, which can bind to specific targets or complementary DNA sequences. The binding kinetics of DNA aptamers is studied by fluorescence quenching at 23 degrees C . A kinetic model for the binding reaction of DNA aptamer, antisense DNA, and ATP target is developed to describe experimental observations. The approach leads to a simple procedure to deduce relevant kinetic reactions and their rate constants. A comparison between theory and experiments indicates that the previously established bimolecular DNA-ATP binding does not provide a complete description of the experimental data. Side reactions such as trimolecular complexation are proposed. Rate constants of the model are determined by comparing the model predictions and experiments. Good agreements between the model and experiments have been obtained. Possible blocking reactions by the misfolded DNA aptamer are also discussed.

We analyze the group-theoretical ramifications of the Nambu-Goldstone [NG] theorem in the self-consistent relativistic variational Gaussian wave functional approximation to spinless field theories. In an illustrative example we show how the Nambu-Goldstone theorem would work in the O(N) symmetric $\phi^4$ scalar field theory, if the residual symmetry of the vacuum were lesser than O(N-1), e.g. if the vacuum were O(N-2), or O(N-3),... symmetric. [This does not imply that any of the "lesser" vacua is actually the absolute energy minimum: stability analysis has not been done.] The requisite number of NG bosons would be (2N - 3), or (3N - 6), ... respectively, which may exceed N, the number of elementary fields in the Lagrangian. We show how the requisite new NG bosons would appear even in channels that do not carry the same quantum numbers as one of N "elementary particles" (scalar field quanta, or Castillejo-Dalitz-Dyson [CDD] poles) in the Lagrangian, i.e. in those "flavour" channels that have no CDD poles. The corresponding Nambu-Goldstone bosons are composites (bound states) of pairs of massive elementary (CDD) scalar fields excitations. As a nontrivial example of this method we apply it to the physically more interesting 't Hooft $\sigma$ model (an extended $N_{f} = 2$ bosonic linear $\sigma$ model with four scalar and four pseudoscalar fields), with spontaneously and explicitly broken chiral $O(4) \times O(2) \simeq SU_{\rm R} (2) \times SU_{\rm L}(2) \times U_{\rm A}(1)$ symmetry., Comment: 17 pages, no figures

We apply a self-consistent relativistic mean-field variational ``Gaussian functional'' (or Hartree) approximation to the linear $��$ model with spontaneously and explicitly broken chiral O(4) symmetry. We set up the self-consistency, or ``gap'' and the Bethe-Salpeter equations. We check and confirm the chiral Ward-Takahashi identities, among them the Nambu-Goldstone theorem and the (partial) axial current conservation [CAC], both in and away from the chiral limit. With explicit chiral symmetry breaking we confirm the Dashen relation for the pion mass and partial CAC. We solve numerically the gap and Bethe-Salpeter equations, discuss the solutions' properties and the particle content of the theory., 20 pages 9 figures

We develop a self-consistent field theory for salt-doped diblock copolymers, such as polyethylene oxide (PEO)–polystyrene with added lithium salts. We account for the inhomogeneous distribution of Li+ ions bound to the ion-dissolving block, the preferential solvation energy of anions in the different block domains, the translational entropy of anions, the ion-pair equilibrium between polymer-bound Li+ and anion, and changes in the χ parameter due to the bound ions. We show that the preferential solvation energy of anions provides a large driving force for microphase separation. Our theory is able to explain many features observed in experiments, particularly the systematic dependence in the effective χ-parameter on the radius of the anions, the observed linear dependence in the effective χ on salt concentration, and increase in the domain spacing of the lamellar phase due to the addition of lithium salts. We also examine the relationship between two definitions of the effective χ parameter, one based on the domain spacing of the ordered phase and the other based on the structure factor in the disordered phase. We argue that the latter is a more fundamental measure of the effective interaction between the two blocks. We show that the ion distribution and the electrostatic potential profile depend strongly on the dielectric contrast between the two blocks and on the ability of the Li+ to redistribute along the backbone of the ion-dissolving block.