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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Water transport through monolayer fullerene membrane

Water transport through nanoporous materials is important in water treatment, desalination, and nanofiltration. Two-dimensional (2D) membranes such as porous graphene have been explored for high-permeance water transport. However, water transport through a new class of 2D membranes based on two-dimensional covalently linked fullerene monolayers has not been fully explored. Here we use classical molecular dynamics simulations to investigate both vapor and liquid water transport through a monolayer fullerene membrane. We find that a quasi-tetragonal phase fullerene membrane possesses the right pore size and geometry that allows fast water vapor transport (∼ 50 g m −2 day −1 Pa −1 ) and water liquid transport (∼ 2.0 g m −2 day −1 Pa −1 ). Furthermore, simulation of sea water transport through the fullerene membrane shows 100 % salt rejection. The much faster vapor transport rate is attributed to the funnel-shaped pore and the optimal size that allows free rotation of water molecules permeating through, while the slower liquid transport is due to the need to desolvate a water molecule to break its hydrogen-bond network across the hydrophobic pore. This work shows the great potential of using monolayer fullerene membranes as 2D membranes for fast and selective water transport.

Desalination↗
DOE OSTI2022

Developing Reaction Chemistry Models from Reactive Molecular Dynamics: TATB

Reactive Molecular Dynamic (RMD) are used to simulate the cook-off chemistry of TATB at a variety of fixed density and fixed temperature conditions. The chemical transformations are monitored using a Coordination Geometry Analysis (CGA) approach which tracks which atom types are bonded to each specific atom. This particularly identifies oxidation state changes that occur during the transformations. Correlations between these different chemical changes are identified using a Non-negative Matrix Factorization (NMF) approach. These identify reduced order chemistry models for the TATB system which contains six components whose concentration profiles are a function of both the temperature and density/pressure. The time histories of these transformations appear to show exponential growth/decay properties that could be fit with Arrhenius rates. These components should form the basis of deflagration rate models for these materials which could then be used in mesoscale simulations to analyze accidental initiation, shock-to-detonation and detonation propagation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Self-Consistent Field Methods for Excited States in Strong Magnetic Fields: A Comparison Between Energy - and Variance-based Approaches

An efficient implementation of geometrical derivatives at the Hartree–Fock (HF) and current-density functional theory (CDFT) levels is presented for the study of molecular structure in strong magnetic fields. The required integral derivatives are constructed using a hybrid McMurchie–Davidson and Rys quadrature approach, which combines the amenability of the former to the evaluation of derivative integrals with the efficiency of the latter for basis sets with high angular momentum. In addition to its application to evaluating derivatives of four-center integrals, this approach is also applied to gradients using the resolution-of-the-identity approximation, enabling efficient optimization of molecular structure for many-electron systems under a strong magnetic field. The CDFT contributions have been implemented for a wide range of density functionals up to and including the meta-GGA level with current-density dependent contributions and (range-separated) hybrids for the first time. Illustrative applications are presented to the OH and benzene molecules, revealing the rich and complex chemistry induced by the presence of an external magnetic field. Challenges for geometry optimization in strong fields are highlighted, along with the requirement for careful analysis of the resulting electronic structure at each stationary point. The importance of correlation effects is examined by comparison of results at the HF and CDFT levels. The present implementation of molecular gradients at the CDFT level provides a cost-effective approach to the study of molecular structure under strong magnetic fields, opening up many new possibilities for the study of chemistry in this regime.

Comparison↗
DOE OSTI2023

Customized Nanostructured Ceramics via Microphase Separation 3D Printing

To date, the restricted capability to fabricate ceramics with independently tailored nano- and macroscopic features has hindered their implementation in a wide range of crucial technological areas, including aeronautics, defense, and microelectronics. In this study, a novel approach that combines self- and digital assembly to create polymer-derived ceramics with highly controlled structures spanning from the nano- to macroscale is introduced. Polymerization-induced microphase separation of a resin during digital light processing generates materials with nanoscale morphologies, with the distinct phases consisting of either a preceramic precursor or a sacrificial polymer. By precisely controlling the molecular weight of the sacrificial polymer, the domain size of the resulting material phases can be finely tuned. Pyrolysis of the printed objects yields ceramics with complex macroscale geometries and nanoscale porosity, which display excellent thermal and oxidation resistance, and morphology-dependent thermal conduction properties. This method offers a valuable technological platform for the simplified fabrication of nanostructured ceramics with complex shapes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

SchrödingerNet: A Universal Neural Network Solver for the Schrödinger Equation

Recent advances in machine learning have facilitated numerically accurate solution of the electronic Schrödinger equation (SE) by integrating various neural network (NN)-based wave function ansatzes with variational Monte Carlo methods. Nevertheless, such NN-based methods are all based on the Born–Oppenheimer approximation (BOA) and require computationally expensive training for each nuclear configuration. In this work, we propose a novel NN architecture, SchrödingerNet, to solve the full electronic-nuclear SE by defining a loss function designed to equalize local energies across the system. This approach is based on a translationally, rotationally and permutationally symmetry-adapted total wave function ansatz that includes both nuclear and electronic coordinates. Furthermore, this strategy not only allows for an efficient and accurate generation of a continuous potential energy surface at any geometry within the well-sampled nuclear configuration space, but also incorporates non-BOA corrections, through a single training process. Comparison with benchmarks of atomic and small molecular systems demonstrates its accuracy and efficiency.

Chemical calculations↗
DOE OSTI2022

Role of High-Spin Species and Pendant Amines in Electrocatalytic Alcohol Oxidation by a Nickel Phosphine Complex

We report the development of active and efficient electrocatalysts for oxidation of alcohols using earth-abundant metals will aid the progress towards a renewable energy economy. Here we present a detailed mechanistic study of electrocatalytic benzyl alcohol oxidation by a molecular nickel complex containing pendant amines using a combination of kinetic studies, NMR spectroscopy, and density functional theory. The catalyst preferentially binds alcohol in high-spin octahedral geometry, but this complex is not readily deprotonated by exogeneous base and inhibits catalysis. Dissociation of one or more solvent ligands returns the complex to a low-spin state that can be deprotonated. Kinetic modeling indicates the off-cycle high-spin intermediate lowers the catalytic turnover frequency by a factor of eight, suggesting that substantial gains in activity can be attained by improvements to the catalyst coordination geometry. In a second finding, we demonstrate the pendant amine of the catalyst only functions as a proton relay for the potential-determining step, oxidation of a nickel hydride intermediate, but does not have a substantial impact on the overall rate for oxidation of benzyl alcohol to benzaldehyde. This result contradicts the common expectation for pendant amines to participate in rate-limiting proton transfer reactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Ultrafast Imaging of Molecules with Electron Diffraction

Photoexcited molecules convert light into chemical and mechanical energy through changes in electronic and nuclear structure that take place on femtosecond timescales. Gas phase ultrafast electron diffraction (GUED) is an ideal tool to probe the nuclear geometry evolution of the molecules and complements spectroscopic methods that are mostly sensitive to the electronic state. GUED is a passive probing tool that does not alter the molecular properties during the probing process and is sensitive to the spatial distribution of charge in the molecule, including both electrons and nuclei. Improvements in temporal resolution have enabled GUED to capture coherent nuclear motions in molecules in the excited and ground electronic states with femtosecond and subangstrom resolution. Here we present the basic theory of GUED and explain what information is encoded in the diffraction signal, review how GUED has been used to observe coherent structural dynamics in recent experiments, and discuss the advantages and limitations of the method.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on U(HO2)2 by Materials Project

UO2(OH)2 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of one molecular hydrogen;dihydrate molecule and one UO2 sheet oriented in the (0, 0, 1) direction. In the UO2 sheet, U6+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of U–O bond distances ranging from 2.05–2.11 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent U6+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent U6+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Computing virtual dark-field X-ray microscopy images of complex discrete dislocation structures from large-scale molecular dynamics simulations

Dark-field X-ray microscopy (DFXM) is a novel diffraction-based imaging technique that non-destructively maps the local deformation from crystalline defects in bulk materials. While studies have demonstrated that DFXM can spatially map 3D defect geometries, it is still challenging to interpret DFXM images of the high-dislocation-density systems relevant to macroscopic crystal plasticity. This work develops a scalable forward model to calculate virtual DFXM images for complex discrete dislocation structure(s) (DDS) obtained from atomistic simulations. Our new DDS-DFXM model integrates a non-singular formulation for calculating the local strain from the DDS and an efficient geometrical optics algorithm for computing the DFXM image from the strain field. We apply the model to complex DDS obtained from a large-scale mol­ecular dynamics simulation of compressive loading on single-crystal silicon. Simulated DFXM images exhibit prominent contrast for dislocation features between the multiple slip systems, demonstrating the potential of DFXM to resolve features from dislocation multiplication. In conclusion, the integrated DDS-DFXM model provides a toolbox for DFXM experimental design and image interpretation in the context of bulk crystal plasticity for a range of measurements across shock plasticity and the broader materials science community.

X-ray imaging↗
DOE OSTI2020

Materials Data on VH17C4S4(O5F3)4 by Materials Project

VH12(S2O9)2(CF3)4H5O2 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of four fluoroform molecules; one molecular hydrogen;dihydrate molecule; and one VH12(S2O9)2 ribbon oriented in the (1, 0, 0) direction. In the VH12(S2O9)2 ribbon, V5+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of V–O bond distances ranging from 2.02–2.04 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.68 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.70 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.69 Å) H–O bond length. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are two inequivalent S+3.50+ sites. In the first S+3.50+ site, S+3.50+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.46 Å) and one longer (1.48 Å) S–O bond length. In the second S+3.50+ site, S+3.50+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.45–1.48 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one H1+ and one S+3.50+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one S+3.50+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one H1+ and one S+3.50+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one S+3.50+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one H1+ and one S+3.50+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one S+3.50+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two H1+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on VH17C4S4(O5F3)4 by Materials Project

VH12(S2O9)2(CF3)4H5O2 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of four fluoroform molecules; one molecular hydrogen;dihydrate molecule; and one VH12(S2O9)2 ribbon oriented in the (1, 0, 0) direction. In the VH12(S2O9)2 ribbon, V5+ is bonded in an octahedral geometry to six O2- atoms. There are two shorter (2.03 Å) and four longer (2.04 Å) V–O bond lengths. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.61 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.67 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.69 Å) H–O bond length. In the fifth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.62 Å) H–O bond length. In the sixth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.58 Å) H–O bond length. There are two inequivalent S+3.50+ sites. In the first S+3.50+ site, S+3.50+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.46 Å) and one longer (1.47 Å) S–O bond length. In the second S+3.50+ site, S+3.50+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.46 Å) and one longer (1.47 Å) S–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one H1+ and one S+3.50+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S+3.50+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one H1+ and one S+3.50+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one H1+ and one S+3.50+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one S+3.50+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one H1+ and one S+3.50+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two H1+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn3P2(HO2)4 by Materials Project

(Zn3P2HO8)2(H2)3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional and consists of four molecular hydrogen molecules and one Zn3P2HO8 framework. In the Zn3P2HO8 framework, there are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a trigonal planar geometry to one H and two equivalent O2- atoms. The Zn–H bond length is 1.55 Å. Both Zn–O bond lengths are 1.86 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent ZnO4 tetrahedra and corners with four equivalent PO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.94–2.03 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent ZnO4 tetrahedra. There is three shorter (1.54 Å) and one longer (1.60 Å) P–O bond length. H is bonded in a single-bond geometry to one Zn2+ atom. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to one Zn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Zn2+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Zn2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Zn2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

2D Retrieval Frameworks for Hot Jupiter Phase Curves

Spectroscopic phase curves provide unique access to the three-dimensional properties of transiting exoplanet atmospheres. However, a modeling framework must be developed to deliver accurate inferences of atmospheric properties for these complex data sets. Here, we develop an approach to retrieve temperature structures and molecular abundances from phase curve spectra at any orbital phase. In the context of a representative hot Jupiter with a large day–night temperature contrast, we examine the biases in typical one-dimensional (1D) retrievals as a function of orbital phase/geometry, compared to two-dimensional (2D) models that appropriately capture the disk-integrated phase geometry. We guide our intuition by applying our new framework on a simulated Hubble Space Telescope (HST)+Spitzer phase curve data set in which the “truth” is known, followed by an application to the spectroscopic phase curve of the canonical hot Jupiter, WASP-43b. We also demonstrate the retrieval framework on simulated James Webb Space Telescope (JWST) phase curve observations. We apply our new geometric framework to a joint fit of all spectroscopic phases, assuming longitudinal molecular abundance homogeneity, resulting in an a factor of 2 improvement in abundances precision when compared to individual phase constraints. With a 1D retrieval model on simulated HST+Spitzer data, we find strongly biased molecular abundances for CH{sub 4} and CO{sub 2} at most orbital phases. With 2D, the day and night profiles retrieved from WASP-43b remain consistent throughout the orbit. JWST retrievals show that a 2D model is strongly favored at all orbital phases. Based on our new 2D retrieval implementation, we provide recommendations on when 1D models are appropriate and when more complex phase geometries involving multiple TP profiles are required to obtain an unbiased view of tidally locked planetary atmospheres.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2020

HAWC+ Far-infrared Observations of the Magnetic Field Geometry in M51 and NGC 891

Stratospheric Observatory for Infrared Astronomy High-resolution Airborne Wideband Camera Plus polarimetry at 154 μm is reported for the face-on galaxy M51 and the edge-on galaxy NGC 891. For M51, the polarization vectors generally follow the spiral pattern defined by the molecular gas distribution, the far-infrared (FIR) intensity contours, and other tracers of star formation. The fractional polarization is much lower in the FIR-bright central regions than in the outer regions, and we rule out loss of grain alignment and variations in magnetic field strength as causes. When compared with existing synchrotron observations, which sample different regions with different weighting, we find the net position angles are strongly correlated, the fractional polarizations are moderately correlated, but the polarized intensities are uncorrelated. We argue that the low fractional polarization in the central regions must be due to significant numbers of highly turbulent segments across the beam and along lines of sight in the beam in the central 3 kpc of M51. For NGC 891, the FIR polarization vectors within an intensity contour of 1500 MJy sr{sup −1} are oriented very close to the plane of the galaxy. The FIR polarimetry is probably sampling the magnetic field geometry in NGC 891 much deeper into the disk than is possible with NIR polarimetry and radio synchrotron measurements. In some locations in NGC 891, the FIR polarization is very low, suggesting we are preferentially viewing the magnetic field mostly along the line of sight, down the length of embedded spiral arms. There is tentative evidence for a vertical field in the polarized emission off the plane of the disk.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2021

Modeling protein structures from predicted contacts with modern molecular dynamics potentials: accuracy, sensitivity, and refinement

Protein structure prediction has become increasingly popular and successful in recent years. An essential step for fragment-free, template-free methods is the generation of a final three-dimensional protein model from a set of predicted amino acid contacts that are often described by interresidue pairwise atomic distances. Here we explore the use of modern, open-source molecular dynamics (MD) engines, which have been continually developed over the last three decades with all-atom Hamiltonians to model biomolecular structure and dynamics, to generate accurate protein structures starting from a set of inferred pairwise distances. Additionally, the ability of MD empirical physical potentials to correct inaccuracies in the predicted geometries is tested. We rigorously characterize the effect of modeling parameters on results, the effect of different amounts of error in the predicted distances on the final structures, and test the ability of post-processing analysis to sort the best models out of a set of statistical replicas. We find that with exact distances and with noisy distances, the method can produce excellent structural models, and that the molecular dynamics force field seems to help correct errors in distance predictions, resisting the effects of applied noise.

Davidson, Russ↗
DOE OSTI2023

Modulating the Extent of Anisotropic Cuprophilicity via High Pressure with Piezochromic Luminescence Sensitization

We report metallophilicity has been widely studied as a fundamental supramolecular interaction. However, the extent and directionality thereof remain controversial. A major obstacle lies in the difficulty to separately control the geometry and chemical composition. Herein, we address this challenge by modulating metallophilicity with mechanical pressure. Using a multinuclear Cu(I) complex as model system, we report anomalous anisotropies of (supra)molecular structures, vibrations, and interaction energies upon isotropic compression as well as concomitant (essentially turn-on) piezochromic luminescence enhancement with ~10 3 modulation. The in situ characterizations indicate opposite behaviors of contact distances and cuprophilic interactions for intermolecular vs intramolecular Cu-Cu pairs under pressure. Theoretical calculations break down the attractive and repulsive forces associated with cuprophilicity, its spontaneous 4p-3d hybridization origin, and direction-dependent interaction strength. The use of isotropic mechanical force reveals the intrinsic anisotropy of metallophilicity in multinuclear systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Metal–Organic Framework-Based Microfluidic Impedance Sensor Platform for Ultrasensitive Detection of Perfluorooctanesulfonate

The growing global concerns to public health from human exposure to perfluorooctanesulfonate (PFOS) requires rapid, sensitive, in-situ detection where current, state-of-the-art techniques are yet to adequately meet sensitivity and selectivity standards of the real-world. This work presents, for the first time, a synergistic approach for the targeted affinity-based capture of PFOS using a porous sorbent probe that enhances detection sensitivity by embedding it on a microfluidic conductive platform. This novel sorbent-containing platform functions as an electrochemical sensor to directly measure PFOS concentration through a proportional change in electrical response (increase in impedance). The extremely high surface area and pore volume of mesoporous metal-organic framework (MOF) Cr-MIL-101 is used as the probe for targeted PFOS capture based on the affinity of the chromium center towards both the fluorine tail groups as well as the sulfonate functionalities as demonstrated by spectroscopic (NMR and XPS) and microscopic (TEM) studies. Answering the need for an ultrasensitive PFOS detection technique, we are embedding these MOF capture probes inside a microfluidic channel, sandwiched between interdigitated microelectrodes (IDµE). The nanoporous geometry increases the signal to noise ratio of interdigitated microelectrodes tremendously increasing sensitivity; this in combination with the ability of the capture probes to interact with the PFOS at the molecular level and effectively transduce that response electrochemically has allowed us achieve a PFOS detection limit of 0.5 ng/L, which is unprecedented for in-situ analytical PFOS sensors and even comparable to quantification limits achieved using state-of-the-art ex situ techniques.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Hydration Mechanisms in Nanoparticle Interaction and Surface Energetics

Work on the project advanced molecular level understanding, prediction and control of nanoscale hydration in salt solutions under electric stimuli or ionic patterning. Permeation of nanoporous electrodes at preset voltage underlies the function of ultracapacitors. Transitory regulation of wetting in nanoporous media by electric field spans an array of applications in materials, energy storage, and separation sciences. The physically related modulation of nanoparticle solubility by surface charges can significantly extend the range of the nanomaterial applications, improve processing techniques, and potentially alleviate environmental concerns. Pore/solution equilibria, and activated kinetics of liquid gating by nanoconfined electrolytes are challenging problems at the forefront of experimental and theoretical research. Addressing these problems from a molecular perspective required the development of state-of-the-art simulation algorithms in statistical mechanics to capture complex processes in open systems under electric control. Parallel studies of wetting and dispersibility of polar and ionizing particles aim to uncover predictive relations between electrowetting, chemical functionalization, and geometry of nanomaterial particles. By nonequilibrium dynamic modeling, we elucidated electrolyte flow in nanochanels and associated electrokinetic energy conversion. Research on the program provided training opportunities for the next generation of scientists in computational chemistry. Insights, and methods from the project implicate broad segment of researchers in energy and nanosciences, materials and surface chemistry.

74 ATOMIC AND MOLECULAR PHYSICS↗