Eccentricity effects on blur and depth perception.

Foveation and (de)focus are two important visual factors in designing near eye displays. Foveation can reduce computational load by lowering display details towards the visual periphery, while focal cues can reduce vergence-accommodation conflict thereby lessening visual discomfort in using near eye displays. We performed two psychophysical experiments to investigate the relationship between foveation and focus cues. The first study measured blur discrimination sensitivity as a function of visual eccentricity, where we found discrimination thresholds significantly lower than previously reported. The second study measured depth discrimination threshold where we found a clear dependency on visual eccentricity. We discuss the study results and suggest further investigation.

Slim near-eye display using pinhole aperture arrays.

We report a new technique for building a wide-angle, lightweight, thin-form-factor, cost-effective, easy-to-manufacture near-eye head-mounted display (HMD) for virtual reality applications. Our approach adopts an aperture mask containing an array of pinholes and a screen as a source of imagery. We demonstrate proof-of-concept HMD prototypes with a binocular field of view (FOV) of 70°×45°, or total diagonal FOV of 83°. This FOV should increase with increasing display panel size. The optical angular resolution supported in our prototype can go down to 1.4-2.1 arcmin by adopting a display with 20-30 µm pixel pitch.

A simple and universal gel permeation chromatography technique for precise molecular weight characterization of well-defined poly(ionic liquid)s.

Poly(ionic liquid)s (PILs) are an important class of technologically relevant materials. However, characterization of well-defined polyionic materials remains a challenge. Herein, we have developed a simple and versatile gel permeation chromatography (GPC) methodology for molecular weight (MW) characterization of PILs with a variety of anions. PILs with narrow MW distributions were synthesized via atom transfer radical polymerization, and the MWs obtained from GPC were further confirmed via nuclear magnetic resonance end group analysis.

Enhanced gas absorption in the ionic liquid 1-n-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([hmim][Tf2N]) confined in silica slit pores: a molecular simulation study.

Two-dimensional NPxyT and isostress-osmotic (N2PxyTf1) Monte Carlo simulations were used to compute the density and gas absorption properties of the ionic liquid (IL) 1-n-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([hmim][Tf2N]) confined in silica slit pores (25-45 Å). Self-diffusivity values for both gas and IL were calculated from NVE molecular dynamics simulations using both smooth and atomistic potential models for silica. The simulations showed that the molar volume of [hmim][Tf2N] confined in 25-45-Å silica slit pores is 12-31% larger than that of the bulk IL at 313-573 K and 1 bar. The amounts of CO2, H2, and N2 absorbed in the confined IL are 1.1-3 times larger than those in the bulk IL because of the larger molar volume of the confined IL compared to the bulk IL. The CO2, N2, and H2 molecules are generally absorbed close to the silica wall where the IL density is very low. This arrangement causes the self-diffusivities of these gases in the confined IL to be 2-8 times larger than those in the bulk IL at 298-573 K. The solubilities of water in the confined and bulk ILs are similar, which is likely due to strong water interactions with [hmim][Tf2N] through hydrogen bonding, so that the molar volume of the confined IL plays a less important role in determining the H2O solubility. Water molecules are largely absorbed in the IL-rich region rather than close to the silica wall. The self-diffusivities of water correlate with those of the confined IL. The confined IL exhibits self-diffusivities larger than those of the bulk IL at lower temperatures, but smaller than those of the bulk IL at higher temperatures. The findings from our simulations are consistent with available experimental data for similar confined IL systems.

CO2 capture properties of lithium silicates with different ratios of Li2O/SiO2: an ab initio thermodynamic and experimental approach.

The lithium silicates have attracted scientific interest due to their potential use as high-temperature sorbents for CO2 capture. The electronic properties and thermodynamic stabilities of lithium silicates with different Li2O/SiO2 ratios (Li2O, Li8SiO6, Li4SiO4, Li6Si2O7, Li2SiO3, Li2Si2O5, Li2Si3O7, and α-SiO2) have been investigated by combining first-principles density functional theory with lattice phonon dynamics. All these lithium silicates examined are insulators with band-gaps larger than 4.5 eV. By decreasing the Li2O/SiO2 ratio, the first valence bandwidth of the corresponding lithium silicate increases. Additionally, by decreasing the Li2O/SiO2 ratio, the vibrational frequencies of the corresponding lithium silicates shift to higher frequencies. Based on the calculated energetic information, their CO2 absorption capabilities were extensively analyzed through thermodynamic investigations on these absorption reactions. We found that by increasing the Li2O/SiO2 ratio when going from Li2Si3O7 to Li8SiO6, the corresponding lithium silicates have higher CO2 capture capacity, higher turnover temperatures and heats of reaction, and require higher energy inputs for regeneration. Based on our experimentally measured isotherms of the CO2 chemisorption by lithium silicates, we found that the CO2 capture reactions are two-stage processes: (1) a superficial reaction to form the external shell composed of Li2CO3 and a metal oxide or lithium silicate secondary phase and (2) lithium diffusion from bulk to the surface with a simultaneous diffusion of CO2 into the shell to continue the CO2 chemisorption process. The second stage is the rate determining step for the capture process. By changing the mixing ratio of Li2O and SiO2, we can obtain different lithium silicate solids which exhibit different thermodynamic behaviors. Based on our results, three mixing scenarios are discussed to provide general guidelines for designing new CO2 sorbents to fit practical needs.

Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort.

Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure-property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO(2) solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO(2) capture but has application in many technological fields.

Theoretical and experimental studies of water interaction in acetate based ionic liquids.

Water interactions in 1-ethyl-3-methylimidazolium acetate ([emim][CH(3)COO]) were studied utilizing classical and ab initio simulation methods. The self-diffusivities for water and the ionic liquid (IL) were studied experimentally using pulse field gradient NMR spectroscopy and correlated with computational results. Water forms hydrogen bonding networks with the ionic liquid, and depending on the concentration of water, there are profound effects on the self-diffusivities of the various species. Both simulation and experiments show that the self-diffusivities for species in the water-[emim][CH(3)COO] system exhibit minima at 40-50 mol% water. Water interaction with the [CH(3)COO](-) anion predominates over the water-water and water-cation interactions at most water concentrations. Simulations further indicate that decreasing water-[CH(3)COO](-) interaction will increase the IL and water self-diffusivities. Self-diffusivities in the water-IL systems are dependent upon the cation in a complex way. Water interactions with [P(4444)][CH(3)COO] are reduced compared to [emim][CH(3)COO]. The [P(4444)](+) cation is bulkier than the [emim](+) cation and has a smaller self-diffusivity, but when water was introduced to [P(4444)] [CH(3)COO], the water-[CH(3)COO](-) hydrogen bonding network in the [P(4444)][CH(3)COO] was much smaller than the one observed in [emim][CH(3)COO].

Toward Standardized Classification of Foveated Displays.

Emergent in the field of head mounted display design is a desire to leverage the limitations of the human visual system to reduce the computation, communication, and display workload in power and form-factor constrained systems. Fundamental to this reduced workload is the ability to match display resolution to the acuity of the human visual system, along with a resulting need to follow the gaze of the eye as it moves, a process referred to as foveation. A display that moves its content along with the eye may be called a Foveated Display, though this term is also commonly used to describe displays with non-uniform resolution that attempt to mimic human visual acuity. We therefore recommend a definition for the term Foveated Display that accepts both of these interpretations. Furthermore, we include a simplified model for human visual Acuity Distribution Functions (ADFs) at various levels of visual acuity, across wide fields of view and propose comparison of this ADF with the Resolution Distribution Function of a foveated display for evaluation of its resolution at a particular gaze direction. We also provide a taxonomy to allow the field to meaningfully compare and contrast various aspects of foveated displays in a display and optical technology-agnostic manner.

Manufacturing Application-Driven Foveated Near-Eye Displays.

Traditional optical manufacturing poses a great challenge to near-eye display designers due to large lead times in the order of multiple weeks, limiting the abilities of optical designers to iterate fast and explore beyond conventional designs. We present a complete near-eye display manufacturing pipeline with a day lead time using commodity hardware. Our novel manufacturing pipeline consists of several innovations including a rapid production technique to improve surface of a 3D printed component to optical quality suitable for near-eye display application, a computational design methodology using machine learning and ray tracing to create freeform static projection screen surfaces for near-eye displays that can represent arbitrary focal surfaces, and a custom projection lens design that distributes pixels non-uniformly for a foveated near-eye display hardware design candidate. We have demonstrated untethered augmented reality near-eye display prototypes to assess success of our technique, and show that a ski-goggles form factor, a large monocular field of view (30o×55o), and a resolution of 12 cycles per degree can be achieved.

Cubosomes from hierarchical self-assembly of poly(ionic liquid) block copolymers.

Cubosomes are micro- and nanoparticles with a bicontinuous cubic two-phase structure, reported for the self-assembly of low molecular weight surfactants, for example, lipids, but rarely formed by polymers. These objects are characterized by a maximum continuous interface and high interface to volume ratio, which makes them promising candidates for efficient adsorbents and host-guest applications. Here we demonstrate self-assembly to nanoscale cuboidal particles with a bicontinuous cubic structure by amphiphilic poly(ionic liquid) diblock copolymers, poly(acrylic acid)-block-poly(4-vinylbenzyl)-3-butyl imidazolium bis(trifluoromethylsulfonyl)imide, in a mixture of tetrahydrofuran and water under optimized conditions. Structure determining parameters include polymer composition and concentration, temperature, and the variation of the solvent mixture. The formation of the cubosomes can be explained by the hierarchical interactions of the constituent components. The lattice structure of the block copolymers can be transferred to the shape of the particle as it is common for atomic and molecular faceted crystals.

Wide Field Of View Varifocal Near-Eye Display Using See-Through Deformable Membrane Mirrors.

Accommodative depth cues, a wide field of view, and ever-higher resolutions all present major hardware design challenges for near-eye displays. Optimizing a design to overcome one of these challenges typically leads to a trade-off in the others. We tackle this problem by introducing an all-in-one solution - a new wide field of view, gaze-tracked near-eye display for augmented reality applications. The key component of our solution is the use of a single see-through, varifocal deformable membrane mirror for each eye reflecting a display. They are controlled by airtight cavities and change the effective focal power to present a virtual image at a target depth plane which is determined by the gaze tracker. The benefits of using the membranes include wide field of view (100° diagonal) and fast depth switching (from 20 cm to infinity within 300 ms). Our subjective experiment verifies the prototype and demonstrates its potential benefits for near-eye see-through displays.

Improving adaptive display with temporally adaptive rendering.

Making computer imagery more responsive and realistic is one of the most basic goals of graphics researchers, and adaptive display is one of the primary means for achieving it. While previous displays have achieved a spatial adaptivity, our research focuses on achieving temporal adaptivity--sampling some regions not only more densely, but also more often. We use closed loop feedback to guide sampling to image regions that change significantly over space or time. Adaptive reconstruction emphasizes older samples in static settings, resulting in sharper images; and new samples in dynamic settings, resulting in images that may be blurry but are up-to-date. In terms of peak signal-to-noise ratio, this prototype produces much better image streams than nonadaptive renderers with the same simulated sampling rates. This new display also offers new opportunities for adapting to user state, allowing adaptive response both where and when it is needed. Our prototype system already responds interactively to changes in the user's viewpoint, it might also respond to any of a number of other indications of user state, including eye tracking, repeatedly manipulated objects, and biometrics.

Molecular simulation and experimental study of CO2 absorption in ionic liquid reverse micelle.

The structure and dynamics for CO2 absorption in ionic liquid reverse micelle (ILRM) were studied using molecular simulations. The ILRM consisted of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) ionic liquid (IL) as the micelle core, the benzylhexadecyldimethylammonium ([BHD](+)) chloride ([Cl](-)) was the cationic surfactant, and benzene was used as the continuous solvent phase in this study. The diffusivity values of this ILRM system were also experimentally determined. Simulations indicate that there is ion exchange between the IL anion ([BF4](-)) and the surfactant anion ([Cl](-)). It was also found that the [bmim][BF4] IL exhibits small local density at the interface region between the IL core and the [BHD](+) surfactant cation layer, which leads to a smaller density for the [bmim][BF4] IL inside the reverse micelle (RM) compared with the neat IL. These simulation findings are consistent with experimental results. Both our simulations and experimental results show that [bmim][BF4] inside the RM diffuses 5-26 times faster than the neat IL, which is partly due to the fast particle diffusion for the ILRM nanodroplet (IL and surfactant) as a whole in benzene solvent compared with neat [bmim][BF4] diffusion. Additionally, it was found that [bmim][BF4] IL solved in benzene diffuses 2 orders of magnitude faster than the neat IL. Lastly, simulations show that CO2 molecules are absorbed in four different regions of the ILRM system, that is, (I) in the IL inner core, (II) in the [BHD](+) surfactant cation layer, (III) at the interface between the [BHD](+) surfactant cation layer and benzene solvent, and (IV) in the benzene solvent. The CO2 solubility was found to decrease in the order II > III ∼ IV > I, while the CO2 diffusivity and permeability decrease in the following order: IV > III > II > I.

Contribution of the acetate anion to CO2 solubility in ionic liquids: theoretical method development and experimental study.

A new theoretical method was developed to compute the Henry's law constant for gas absorption in a solvent through strong nonphysical interactions. The new method was created by expanding the test particle insertion method typically applied to physisorbing systems to account for the strong intermolecular interactions present in chemisorbing systems. By using an ab initio (AI)-based Boltzmann-averaged potential to model the interaction between CO2 and the tetra-n-butylphosphonium acetate ([P4444][CH3COO]) ionic liquid, the total Henrys's law constant at 298 K was computed to be 0.011 to 0.039 bar, reasonably comparable to the experimental value of 0.18 bar measured in this work. Three different AI potentials were used to verify the applicability of this approach. In contrast, when a classical force field (FF) was used to describe the interaction between CO2 and [P4444][CH3COO], the Henry's law constant was computed to be 27 bar, significantly larger than the experimental value. The classical FF underestimates the CO2-[P4444][CH3COO] interaction compared with the AI calculations, which in turn leads to the smaller simulated CO2 solubility. Simulations further indicate that the CO2 interaction with the [CH3COO](-) anion is much stronger than with the [P4444](+) cation. This result strongly suggests that the large CO2 solubility in [P4444][CH3COO] is due to the strong CO2-[CH3COO](-) interaction.

Toward a Materials Genome Approach for ionic liquids: synthesis guided by ab initio property maps.

The Materials Genome Approach (MGA) aims to accelerate development of new materials by incorporating computational and data-driven approaches to reduce the cost of identification of optimal structures for a given application. Here, we use the MGA to guide the synthesis of triazolium-based ionic liquids (ILs). Our approach involves an IL property-mapping tool, which merges combinatorial structure enumeration, descriptor-based structure representation and sampling, and property prediction using molecular simulations. The simulated properties such as density, diffusivity, and gas solubility obtained for a selected set of representative ILs were used to build neural network models and map properties for all enumerated species. Herein, a family of ILs based on ca. 200,000 triazolium-based cations paired with the bis(trifluoromethanesulfonyl)amide anion was investigated using our MGA. Fourteen representative ILs spreading the entire range of predicted properties were subsequently synthesized and then characterized confirming the predicted density, diffusivity, and CO2 Henry's Law coefficient. Moreover, the property (CO2, CH4, and N2 solubility) trends associated with exchange of the bis(trifluoromethanesulfonyl)amide anion with one of 32 other anions were explored and quantified.

Carbon dioxide (CO2) absorption behavior of mixed matrix polymer composites containing a flexible coordination polymer.

Mixed matrix membranes (MMMs) comprised of metal organic frameworks (MOFs) dispersed in organic polymers are popular materials under study for potential applications in gas separations. However, research on MMMs containing structurally dynamic sorbents known as flexible MOFs has only very recently appeared in the literature. The thermodynamic requirements of the structure transition between the low porosity and high porosity phases of flexible MOFs may provide a mechanism for high adsorption selectivity in these materials. A fundamental question in MMMs containing flexible MOFs is how the constraint of the polymer matrix on the intrinsic expansion of the flexible MOF particles that occurs during gas adsorption might affect the thermodynamics of this structural phase transition and influence the gas adsorption properties of the embedded MOF. To investigate the fundamental nature of this flexible MOF-polymer interface, thin films of ~20 um thickness were prepared using the flexible linear chain coordination polymer catena-bis(dibenzoylmethanato)-(4,4'bipyridyl)nickel(II) "Ni(Bpy)(DBM)(2)" embedded as 35 wt% dispersions in Matrimid®, polystyrene, and polysulfone. The adsorption of CO(2) in the polymers and embedded particles was studied using in situ ATR-FTIR spectroscopy and variable temperature volumetric CO(2) adsorption/desorption isotherms. Interestingly, no effect of the polymer matrix on the gas adsorption behavior of the embedded Ni(Bpy)(DBM)(2) particles was observed. The composite samples all showed the same threshold pressures for CO(2) absorption and desorption hysteresis associated with the structural phase change in the polymer embedded Ni(Bpy)(DBM)(2) particles as was observed in the pristine polycrystalline sample. The current results contrast those recently reported for a MMM containing the flexible MOF "NH(2)-MIL-53" where a significant increase in the threshold pressure for CO(2) adsorption associated with the structural phase change of the MOF was observed in the MMM as compared to the isolated MOF. The conflicting behaviors in these two systems are rationalized from the large differences in unit cell expansions between the two MOFs during the CO(2) adsorption process.

Nuclear spin relaxation and molecular interactions of a novel triazolium-based ionic liquid.

Nuclear spin relaxation, small-angle X-ray scattering (SAXS), and electrospray ionization mass spectrometry (ESI-MS) techniques are used to determine supramolecular arrangement of 3-methyl-1-octyl-4-phenyl-1H-triazol-1,2,3-ium bis(trifluoromethanesulfonyl)imide [OMPhTz][Tf2N], an example of a triazolium-based ionic liquid. The results obtained showed first-order thermodynamic dependence for nuclear spin relaxation of the anion. First-order relaxation dependence is interpreted as through-bond dipolar relaxation. Greater than first-order dependence was found in the aliphatic protons, aromatic carbons (including nearest neighbors), and carbons at the end of the aliphatic tail. Greater than first order thermodynamic dependence of spin relaxation rates is interpreted as relaxation resulting from at least one mechanism additional to through-bond dipolar relaxation. In rigid portions of the cation, an additional spin relaxation mechanism is attributed to anisotropic effects, while greater than first order thermodynamic dependence of the octyl side chain's spin relaxation rates is attributed to cation-cation interactions. Little interaction between the anion and the cation was observed by spin relaxation studies or by ESI-MS. No extended supramolecular structure was observed in this study, which was further supported by MS and SAXS. nuclear Overhauser enhancement (NOE) factors are used in conjunction with spin-lattice relaxation time (T1) measurements to calculate rotational correlation times for C-H bonds (the time it takes for the vector represented by the bond between the two atoms to rotate by one radian). The rotational correlation times are used to represent segmental reorientation dynamics of the cation. A combination of techniques is used to determine the segmental interactions and dynamics of this example of a triazolium-based ionic liquid.

Amino acid-functionalized ionic liquid solid sorbents for post-combustion carbon capture.

Amino acid ionic liquids (AAILs) are potential green substitutes of aqueous amine solutions for carbon dioxide (CO2) capture. However, the viscous nature of AAILs greatly hinders their further development in CO2 capture applications. In this contribution, 1-ethyl-3-methylimidazolium lysine ([EMIM][Lys]) was synthesized and immobilized into a porous poly(methyl methacrylate) (PMMA) microsphere support for post-combustion CO2 capture. The [EMIM][Lys] exhibited good thermal stability and could be facilely immobilized into porous microspheres. Significantly, the [EMIM][Lys]-PMMA sorbents retained their porous structure after [EMIM][Lys] loading and exhibited fast kinetics. When exposed to CO2 at 40 °C, [EMIM][Lys]-PMMA sorbent exhibited the highest CO2 capacity compared to other counterparts studied and achieved a capacity of 0.87 mol/(mol AAIL) or 1.67 mmol/(g sorbent). The capture process may be characterized by two stages: CO2 adsorption on the surface of sorbent and CO2 diffusion into sorbent for further adsorption. The calculated activation energies of the two-stage CO2 sorption were 4.1 and 4.3 kJ/mol, respectively, indicating that, overall, the CO2 can easily adsorb onto this sorbent. Furthermore, multiple cycle tests indicated that the developed sorbents had good long-term stability. The developed sorbent may be a promising candidate for post-combustion CO2 capture.

Theoretical and experimental studies of CO2 and H2 separation using the 1-ethyl-3-methylimidazolium acetate ([emim][CH3COO]) ionic liquid.

The performance of [emim][CH(3)COO] ionic liquid (IL) to separate mixtures of CO(2) and H(2) is studied using both classical and ab initio simulation methods and experiments. Simulations show that H(2) solubility and permeability in [emim][CH(3)COO] are quite low with Henry's law constants about 1 × 10(4) bar and permeabilities in the range 29-79 barrer at 313-373 K. In the case of CO(2) absorption in [emim][CH(3)COO], ab initio molecular dynamics simulations predict two types of CO(2) absorption states. In type I state, CO(2) molecules interact with the [CH(3)COO](-) anion through strong complexation leading to high CO(2) solubility. The C atom of CO(2) is located close to the O atoms of the [CH(3)COO](-) anion with an average distance of about 1.61 Å. The CO(2) bond angle (θ(OCO)) is about 138°, significantly perturbed from that of an isolated linear CO(2). In type II state, the CO(2) molecule maintains a linear configuration and is located at larger separations (>2.2 Å) from the [CH(3)COO](-) anion. The weaker interaction of CO(2) with the [CH(3)COO](-) anion in type II state is similar to the one observed when CO(2) absorbs in [bmim][PF(6)]. Simulations further demonstrate that the [emim](+) cation competes with CO(2) to interact with the [CH(3)COO](-) anion. The predicted high CO(2) permeability and low H(2) permeability in [emim][CH(3)COO] are also verified by our experiments. The experimental CO(2) permeability in [emim][CH(3)COO] is in the range of 1325-3701 barrer, and high experimental CO(2)/H(2) permeability selectivities of 21-37 at 313-373 K are observed. We propose that by replacing [emim](+) cation with 1-butyl-1-methylpyrrolidinium ([PY(14)](+)) further enhancement of CO(2) solubility in [PY(14)][CH(3)COO] IL will be obtained as well as good performance to separate CO(2) and H(2).

Density functional theory studies on the electronic, structural, phonon dynamical and thermo-stability properties of bicarbonates MHCO(3), M = Li, Na, K.

The structural, electronic, phonon dispersion and thermodynamic properties of MHCO(3) (M = Li, Na, K) solids were investigated using density functional theory. The calculated bulk properties for both their ambient and the high-pressure phases are in good agreement with available experimental measurements. Solid phase LiHCO(3) has not yet been observed experimentally. We have predicted several possible crystal structures for LiHCO(3) using crystallographic database searching and prototype electrostatic ground state modeling. Our total energy and phonon free energy (F(PH)) calculations predict that LiHCO(3) will be stable under suitable conditions of temperature and partial pressures of CO(2) and H(2)O. Our calculations indicate that the [Formula: see text] groups in LiHCO(3) and NaHCO(3) form an infinite chain structure through O⋯H⋯O hydrogen bonds. In contrast, the [Formula: see text] anions form dimers, [Formula: see text], connected through double hydrogen bonds in all phases of KHCO(3). Based on density functional perturbation theory, the Born effective charge tensor of each atom type was obtained for all phases of the bicarbonates. Their phonon dispersions with the longitudinal optical-transverse optical splitting were also investigated. Based on lattice phonon dynamics study, the infrared spectra and the thermodynamic properties of these bicarbonates were obtained. Over the temperature range 0-900 K, the F(PH) and the entropies (S) of MHCO(3) (M =Li, Na, K) systems vary as F(PH)(LiHCO(3)) > F(PH)(NaHCO(3)) > F(PH)(KHCO(3)) and S(KHCO(3)) > S(NaHCO(3)) > S(LiHCO(3)), respectively, in agreement with the available experimental data. Analysis of the predicted thermodynamics of the CO(2) capture reactions indicates that the carbonate/bicarbonate transition reactions for Na and K could be used for CO(2) capture technology, in agreement with experiments.