Orientation Of Molecules Research Articles

Polymer-Dispersed Liquid Crystal Gas Sensor for Acetone Detection Using Correlated Laser Speckles

Acetone is a widely used volatile organic compound in various industries, and several gas sensors have been developed for its detection and real-time monitoring. This study reported a novel method for determining the acetone vapor concentration based on correlated laser speckles using polymer-dispersed liquid crystals (PDLCs). Here, PDLC films comprising a mixture of the thermotropic nematic liquid crystal (LC) and ultraviolet-curable polymers were fabricated using different LC mass ratios and ultraviolet curing conditions. The laser beam was transmitted through the PDLC film to generate scattered light and speckles. When the PDLC film was exposed to the acetone vapor, the acetone molecules diffused into the PDLC film and interacted with the LC molecules, modifying the orientation of the LC molecules and the equivalent refractive index of the LC droplets. This in turn decreased the correlation coefficient of the speckle images. The experimental results indicated that the PDLC gas sensor was selectively sensitive to different concentrations of the acetone vapor, ranging from 1 800 ppm to 3 200 ppm. In comparison with traditional LC gas sensors that use a polarizing microscope to detect the change in brightness of the modulated light field, the proposed method is simpler, less expensive, and more robust under external disturbances such as vibrations.

Electrically Tunable Spin‐Orbit Coupled Photonic Lattice in a Liquid Crystal Microcavity

AbstractA 1D photonic crystal is created with strong polarization dependence and tunable by an applied electric field. This is accomplished in a planar microcavity by embedding a cholesteric liquid crystal (LC), which spontaneously forms a uniform lying helix (ULH). The applied voltage controls the orientation of the LC molecules and, consequently, the strength of a polarization‐dependent periodic potential. It leads to opening or closing of photonic bandgaps in the dispersion of the massive photons in the microcavity. In addition, when the ULH structure possesses a molecular tilt, it induces a spin‐orbit coupling between the lattice bands of different parity. This interband spin‐orbit coupling (ISOC) is analogous to optical activity and can be treated as a synthetic non‐Abelian gauge potential. Finally, it is showed that doping the LC with dyes allows us to achieve lasing that inherits all the above‐mentioned tunable properties of LC microcavity, including dual and circularly‐polarized lasing.

Application of eco-friendly material as an inexpensive adsorbent for methyl violet dye removal: experimental, response surface methodology and statistical physics

Methyl Violet (MV) removal from aqueous solutions is studied using an Algerian Bentonite sample as a low-cost adsorbent. SEM-EDX, X-ray diffraction, and chemical composition characterized the adsorbent material. The modeling and optimization study of MV adsorption using artificial neural network (ANN) and response surface methodology (RSM) were also examined. The effects of pH, contact time, dye concentration, and temperature are all considered. The adsorption kinetics results are adjusted to best fit the pseudo-second-order model. Langmuir-Freundlich and Langmuir models well describe the experimental data with an adsorption capacity of 472 mg g−1. The calculated thermodynamic data demonstrates that adsorption is spontaneous and endothermic. Desorption studies with methanol indicate that the adsorbent could successfully retain MV, even after five cycles. The statistical physics theory indicates the non-parallel orientation of the MV molecule’s adsorption. The adsorption energies varied from 13.99 to 17.60 kJ mol−1, revealing the physical adsorption systems. From these results, it can be considered that the raw Algerian bentonite sample tested herein is effective in removing MV from aqueous solutions and may be used as an alternative to high-cost commercial adsorbents.

The Interplay between Dynamics and Structure on the Dielectric Tensor of Nanoconfined Water: Surface Charge and Salinity Effect.

Under confinement, the water dielectric constant is a second-order tensor with an abnormally low out-of-plane element. In our work, we investigate the dielectric tensor of an aqueous NaCl solution confined by a quartz slit-pore. The static dielectric constant is determined from local polarization density fluctuations via molecular dynamics simulations. In a pioneering investigation, we evaluate not only the effect of salinity but also surface charge. The parallel dielectric constant decreases with salinity due to dielectric saturation. From a dynamic perspective, the relaxation of water dipoles is slower within the hydration shells of ions. An anisotropic arrangement on the quartz surface results in preferred orientations of interfacial water molecules. By embedding charge, the surface structure changes, and extra dipole fluctuations in one direction may develop anisotropy in the parallel dielectric constant at the interface. Both surface charge and salinity increase the perpendicular dielectric constant. Nevertheless, the surface charge effect is more pronounced and may even recover the bulk dielectric constant value. The electric field established by the charged surface may disturb the planar hydrogen bond network at the interface, increasing out-of-plane dipolar fluctuations. Our work advances the knowledge of confined dielectric behavior, shedding light on the key role that charged surfaces play.

Intrinsic Rashba Effect in Stable Configurations of Two-Dimensional (PEA)2PbI4.

Halide perovskites (HPs) are crystalline solids that feature a unique softness, absent in conventional semiconducting materials. In recent years, this softness has been pivotal to many properties in these materials, in both static and dynamic regimes. Here, we focus on the two-dimensional (2D) (PEA)2PbI4 crystal. We employ extensive density functional theory calculations and structural analysis to uncover a rich mosaic of ground-state configurations, identifying several stable configurations with distinct electronic properties. Our study uncovers an intrinsic Rashba effect within a structure traditionally considered as globally centrosymmetric, presenting a challenge to conventional understanding in the field. The observed effect emerges from a local symmetry-breaking induced by specific spatial orientations of the organic PEA molecules. This intrinsic Rashba effect, observed in select configurations, underscores the nuanced symmetrical complexities of 2D HPs and highlights their potential for spin-related applications. Additionally, our investigation demonstrates the exceptional flexibility of 2D HPs, as evidenced by an observed significant tolerance toward single-molecule rotations. This flexibility suggests potential pathways for smoother transitions between different molecular domains within these materials. Overall, our findings emphasize the intricate interplay between the organic/inorganic counterparts and the electronic properties in 2D HPs, paving the way for further exploration and exploitation of their unique characteristics in various optoelectronic and spintronic applications.

The Effect of Salinity on the Dielectric Permittivity of Nanoconfined Geofluids.

Nanoporosity is a characteristic feature of geological formations that provides potential pathways for geofluids to meander and interact with minerals. Confinement of water within nanopores leads to unique phenomena. The dielectric constant of water becomes anisotropic and adopts tensorial properties rather than remaining a scalar value. In such nanoconfinement, it has been found that the permittivity of water decreases perpendicularly and increases parallel to the interface. As geofluids are rarely pure water in nature, being a water-salt(-gas) mixture within the Earth, it becomes pivotal to examine how these additional constituents of water affect the permittivity of fluids confined within the nanopores of rocks. In this study, we present the calculation of the permittivity of saline water in calcite slit nanopores using molecular dynamics simulations under low-pressure-temperature conditions. The dielectric properties are weakly dependent on salinity for both the perpendicular and parallel dielectric permittivity components. We analyzed the atomic charge and polarization density of the fluid perpendicular to the nanochannel walls and the orientation of water molecules' dipole inside the nanochannel. From our analysis, most of these factors were generally not altered significantly in the presence of salinity. These findings are significant because they enable us to use well-studied pure water properties under nanoconfinement to determine the geochemical behavior of fluids within natural nanoporous systems.

Adsorption of sarin on zigzag boron-nitride nanotubes (BNNTs) via DFT

To find a suitable sensitivity sensor for sarin molecule (GB) as a nerve agent, we have compared and contrasted the adsorption behavior of it on the exterior surfaces of the (4,0), (5,0), (6,0), (7,0) and (8,0) BNNTs, at B3LYP/6-311+G*. The equilibrium distances (RGB-BNNT), Eads., FMOs, Eg, DOS, D.M. (μ) and reactivity index are estimated for the adsorption process of GB on these BNNTs. The RGB-BNNT, Eads. and the electronic properties of the BNNTs are depend on the BNNT diameter and orientation of the GB molecule outside BNNTs. The shorter RGB-BNNT of 1.61 Å and Eads. of −12.58 kcal/mol reveals that the 40O conformer is the most favorable configuration in which oxygen atom of PO in GB molecule is situated above a boron atom of (4,0) BNNT. The longer RGB-BNNT of 3.81 Å and Eads. of −2.31 kcal/mol exhibits that the 80F conformer is the least favorable configuration in which florin atom of PF in GB molecule is situated above a boron atom of (8,0) BNNT. However, adsorption process is exothermic. By increasing of the BNNT’s diameter and in going from (4،0) to (8،0) GB-BNNT complex either for the orientated PO or PF site; Eg and D.M. values are increased via the adsorption process. Henceforth, the designed 40O and 80F systems energetically are anticipated as the most and the least favorable complex, via the strong chemisorption and physisorption, respectively.

Probing Host‐Guest Inclusion Complex of DHP with β‐CD in Augmenting Bioavailability to Boost Biochemical Applications Optimized by Physicochemical and Molecular Docking

AbstractThis research aims to develop the inclusion complex of 2, 4‐diamino‐6‐hydroxypyrimidine (DHP) with β‐cyclodextrin (β‐CD) using an inclusion process, and to investigate the effect of inclusion on the photo stability and bioactivity of DHP. The formation of DHP‐β‐CD inclusion complex has been examined by means of physicochemical as well as spectroscopic techniques (1H NMR, FT‐IR, PXRD and SEM) suggesting the successful inclusion of the DHP molecule into the β‐CD cavity. The 1 : 1 stoichiometry of the inclusion complex was validated through Job's plot. β‐CD displayed a fairly strong affinity (Ka =889.67 M−1) for DHP, indicating that the binding process is thermodynamically feasible. A molecular docking study speculated the most preferred orientation of DHP molecule within the binding pocket of β‐CD cavity. The photostability of DHP was found to improve on complexation with β‐CD. In vitro antibacterial activity test demonstrated that the DHP‐β‐CD inclusion complex displayed better activity than pure DHP. DHP‐β‐CD inclusion complex (IC50 =240.04 μM) also exhibited relatively significant in vitro cytotoxic activity than pure DHP towards the human kidney cancer cell line (ACHN). These results reveals that the inclusion of DHP using β‐CD could lead to stabilization of DHP and efficient display of its bioactivity.

"Seeing Is Believing": How Neutron Crystallography Informs Enzyme Mechanisms by Visualizing Unique Water Species.

Hydrogen is the lightest atom and composes approximately half of the atomic content in macromolecules, yet their location can only be inferred or predicted in most macromolecular structures. This is because hydrogen can rarely be directly observed by the most common structure determination techniques (such as X-ray crystallography and electron cryomicroscopy). However, knowledge of hydrogen atom positions, especially for enzymes, can reveal protonation states of titratable active site residues, hydrogen bonding patterns, and the orientation of water molecules. Though we know they are present, this vital layer of information, which can inform a myriad of biological processes, is frustratingly invisible to us. The good news is that, even at modest resolution, neutron crystallography (NC) can reveal this layer and has emerged this century as a powerful tool to elucidate enzyme catalytic mechanisms. Due to its strong and coherent scattering of neutrons, incorporation of deuterium into the protein crystal amplifies the power of NC. This is especially true when solvation and the specific participation of key water molecules are crucial for catalysis. Neutron data allow the modeling of all three atoms in water molecules and have even revealed previously unobserved and unique species such as hydronium (D3O+) and deuteroxide (OD-) ions as well as lone deuterons (D+). Herein, we briefly review why neutrons are ideal probes for identifying catalytically important water molecules and these unique water-like species, limitations in interpretation, and four vignettes of enzyme success stories from disparate research groups. One of these groups was that of Dr. Chris G. Dealwis, who died unexpectedly in 2022. As a memorial appreciation of his scientific career, we will also highlight his interest and contributions to the neutron crystallography field. As both the authors were mentored by Chris, we feel we have a unique perspective on his love of molecular structure and admiration for neutrons as a tool to query those structures.

Proton-Driven Dynamic Behavior of Nanoconfined Water in Hydrophilic MXene Sheets.

Liquid water under nanoscale confinement has attracted intensive attention due to its pivotal role in understanding various phenomena across many scientific fields. MXenes serve an ideal paradigm for investigating the dynamic behaviors of nanoconfined water in a hydrophilic environment. Combining deep neural networks and an active learning scheme, here we elucidate the proton-driven dynamics of water molecules confined between V2CTx sheets using molecular dynamics simulation. Firstly, we have found that the Eigen and Zundel cations can inhibit water-induced oxidation by adjusting the orientation of water molecules, thus proposing a general antioxidant strategy. Besides, we also identified a hexagonal ice phase with abnormal bonding rules at room temperature, rather than only at ultralow temperatures as other studies reported, and further captured the proton-induced water phase transition. This highlighted the importance of protons in the maintaining stable crystal phase and phase transition of water. Furthermore, we discussed the conversions of different water structures and water diffusivity with changing proton concentrations in detail. The results provide useful guidance in practical applications of MXenes including developing antioxidant strategies, identifying novel 2D water phases and optimizing energy storage and conversion.

Insights into the Hydration Layer of Reduced Graphene Oxides: A Computational Stud.

Reduced graphene oxide (rGO) has emerged as a versatile material with diverse applications, particularly in aqueous environments. Understanding its interactions with water molecules is crucial for various fields, ranging from energy storage to sensing. In this study, we investigate the behavior of graphene and rGO in water, focusing on elucidating their wetting properties and the influence of oxygen-containing functional groups. Through extensive molecular dynamics simulations, we analyze the orientation and electrostatic dipole of water molecules near the rGO interface, revealing a direct correlation between rGO hydrophilicity and oxidation level. Specifically, we observe stronger hydrogen bonding networks near higher coverage rGO monolayers, indicating enhanced hydrophilicity. Furthermore, by studying water confined between rGO layers, we find uniform water transport with lateral self-diffusion coefficients comparable to bulk water, highlighting the potential of rGO membranes in various applications. Our findings provide insights into the atomic-scale interactions governing rGO-water interfaces, paving the way for the rational design of graphene-based materials for application in aqueous environments.

Nanostructured Polymer-Dispersed Liquid Crystals Using a Ferroelectric Smectic A Liquid Crystal.

Nanostructured polymer-dispersed liquid crystals (nano-PDLCs) are transparent and optically isotropic materials in which submicron-sized liquid crystal (LC) domains are dispersed within a polymer matrix. Nano-PDLCs can induce birefringence by applying an electric field (E-field) based on the reorientation of the LC molecules. If nano-PDLCs are utilized as light-scattering-less birefringence memory materials, it is necessary to suppress the relaxation of the LC molecule orientation after the removal of the E-field. We focused on the ferroelectric smectic A (SmA) phase to suppress the relaxation of LC molecules, owing to its layered structure and high viscosity. Although nano-PDLCs require a strong E-field to reorient their LC molecules because of the anchoring effect at the LC/polymer interface, the required field strength can be reduced using a ferroelectric smectic A (SmAF) LC with a large dielectric constant. In this study, we fabricated a nano-PDLC by shining an ultraviolet light on a mixture comprised an SmAF LC, photocurable monomers, and a photo-initiator. The electro-birefringence effect was evaluated using polarizing optical microscopy. After the removal of the E-field, an enhanced memory effect was observed in the sample using SmAF LC compared with nematic LC-based nano-PDLCs.

Numerical evaluation of orientation averages and its application to molecular physics.

In molecular physics, it is often necessary to average over the orientation of molecules when calculating observables, in particular when modeling experiments in the liquid or gas phase. Evaluated in terms of Euler angles, this is closely related to integration over two- or three-dimensional unit spheres, a common problem discussed in numerical analysis. The computational cost of the integration depends significantly on the quadrature method, making the selection of an appropriate method crucial for the feasibility of simulations. After reviewing several classes of spherical quadrature methods in terms of their efficiency and error distribution, we derive guidelines for choosing the best quadrature method for orientation averages and illustrate these with three examples from chiral molecule physics. While Gauss quadratures allow for achieving numerically exact integration for a wide range of applications, other methods offer advantages in specific circumstances. Our guidelines can also be applied to higher-dimensional spherical domains and other geometries. We also present a Python package providing a flexible interface to a variety of quadrature methods.

Study on the effect of spatial adsorption orientation on the preferential selection mechanism of dust suppression surfactants

Surfactants are widely used in the field of coal dust control. However, the dust suppression effect of different surfactants varies significantly, and the preferential selection mechanism of dust suppressants for mining is not clear. In this study, the water/surfactant/lignite system was constructed by molecular simulation to investigate the adsorption behavior of surfactants with different structures on the lignite surface at the molecular level. The reasons for the differences in the wettability adsorption of sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS), fatty alcohol polyoxyethylene ether-9 (AEO-9), and alkyl polyglycoside (APG1214) on the lignite surface were also investigated based on the quantum chemical calculations and macroscopic experimental analysis. The results showed that the adsorption orientation of surfactant molecules at the solid–liquid interface exerted a pivotal influence on the surface wettability of lignite. According to molecular orbital and electrostatic potential analysis, surfactant molecules with LUMO distributed in the tail chain were more inclined to form a positive adsorption orientation than that concentrated in the polar headgroups; and the stronger the interaction between the polar headgroups and the coal surface with the like charge, the more stable the adsorption of surfactant molecules with the positive arrangement at the interface was. Furthermore, the stronger potential difference between SDS molecules and the hydroxyl-rich structure of the APG1214 molecules are conducive to the formation of hydrogen bonds with water molecules. Wettability experiments showed that the ability of surfactants to improve the wettability of coal dust was positively correlated with the adsorption orientation.

Fractional Talbot Lithography for Predesigned Large-Area Liquid-Crystal Alignment

To address the increasing demands for cost-effective, large-area, and precisely patterned alignment of liquid crystals, a fractional Talbot lithography alignment technique was proposed. A light intensity distribution with a double spatial frequency of a photomask could be achieved based on the fractional Talbot effect, which not only enhanced the resolution of lithography but also slashed system costs with remarkable efficiency. To verify the feasibility of the alignment method, we prepared a one-dimensional polymer grating as an alignment layer. A uniform alignment over a large area was achieved thanks to the perfect periodicity and groove depth of several hundred nanometers. The anchoring energy of the alignment layer was 1.82 × 10−4 J/m2, measured using the twist balance method, which surpassed that of conventional rubbing alignment. Furthermore, to demonstrate its ability for non-uniform alignment, we prepared polymer concentric rings as an alignment layer, resulting in a liquid-crystal q-plate with q = 1 and α0 = π/2. This device, with a wide tuning range (phase retardation of ~6π @ 633 nm for 0 to 5 V), was used to generate special optical fields. The results demonstrate that this approach allows for the uniform large-area orientation of liquid-crystal molecules with superior anchoring energy and customizable patterned alignment, which has extensive application value in liquid-crystal displays, generating special optical fields and intricate liquid-crystal topological defects over a large area.

Investigation of the effect of salts on dye wastewater separation performance in TpPa-1 membrane via molecular dynamics simulation

The rapid progress in science and technology increases the demand for dyes and results in the pollution of dye wastewater. Recently, covalent organic frameworks (COFs) have been suggested as a promising candidate for wastewater treatment. The influence of inorganic salt ions on the transport and separation processes of dye wastewater is poorly understood. In this work, the transport and separation mechanisms of dyes are investigated via nonequilibrium molecular dynamics simulations (NEMD). It is found that the inorganic salts enhance the rejection rate of different dyes in TpPa-1 membranes. The fundamental reason for this phenomenon is the hindrance caused by inorganic salt ions, which change the orientation of dye molecules as they pass through the pore channels of the TpPa-1 membrane. As a result, the dye molecules show a greater tendency to form π–π interaction with the TpPa-1 membrane surface, which accelerates their adsorption.

Theoretical insights into the diverse stabilizing effects of fenchyl alcohol/thymol eutectic solvent on carotenoids

Carotenoids, a class of vital natural pigments, are known for their antioxidant properties and are integral to various industrial applications. However, their instability during processing and storage has limited their broader utilization. This study investigated the stabilizing effects of a fenchyl alcohol/thymol-based deep eutectic solvent (DES) on a spectrum of carotenoids, including lutein, zeaxanthin, astaxanthin, and β-carotene. Through a combination of ab initio molecular dynamics (AIMD) simulations and quantum chemical calculations, we elucidated the molecular interactions and stabilization mechanisms within the DES environment (methanol as the benchmark). Our findings reveal that the DES could exert varying degrees of influence on the stability of different types of carotenoids. The temperature-dependent behavior of carotenoids in the DES suggested a complex interplay between hydrogen bonding, dispersion forces, and the inherent structural properties of carotenoids. AIMD simulations provided a detailed picture of the structural organization and hydrogen bond network topology within the DES, highlighting the role of temperature on the stability and orientation of solvent molecules around carotenoids. Energy decomposition analysis (EDA), Hirshfeld surface analysis, and visual study of interactions further dissected the non-covalent interactions, emphasizing the significance of electrostatic and dispersion forces-driven non-covalent interactions (van der Waals dispersion interactions) in stabilizing carotenoids within the DES matrix. In comparison to methanol, the interactions between components of the eutectic system and the target molecules demonstrate enhanced dynamism, increased complementarity, and a greater variety of interaction patterns. This research presented a novel perspective on the use of DESs for the stabilization of carotenoids, offering potential solutions to enhance their industrial applicability and performance. The insights gained from this study are crucial for the development of sustainable and eco-friendly solvent systems, aligning with the growing demand for green chemistry in the pharmaceutical, cosmetic, and food industries.

Enhancement of organic field-effect transistor performance via precision molecular alignment of a P4T2F-HD-based conjugated polymer

This study conducts a detailed exploration of how the orientation of molecules affects the efficiency of organic field-effect transistors (OFETs), with a particular focus on a new conjugated polymer, P4T2F-HD. The study examines the fabrication of both large-scale, anisotropically oriented thin films and non-oriented, isotropic thin films of P4T2F-HD through two separate approaches: the Unidirectional Film Transfer Method (UFTM) for oriented films and spin-coating for isotropic films. Results indicate that UFTM notably excels in directing the molecular alignment of P4T2F-HD across extensive areas, thereby creating anisotropic thin films, whereas spin-coating yields isotropic thin films lacking specific orientation. Further investigation into the properties of these films through various analytical techniques sheds light on the role of molecular orientation in influencing their electronic characteristics. OFETs fabricated with anisotropically oriented P4T2F-HD films exhibit markedly improved performance, characterized by higher charge carrier mobility and enhanced electrical stability, in comparison to their isotropic counterparts. The study evidences that the directional arrangement of macromolecules plays a pivotal role in OFETs functionality, with UFTM-derived films demonstrating a significant leap in field-effect mobility—showing an over 100-fold improvement over spin-coated films. This boost is linked to the effective charge transmission along the polymer chains, enabled by precise molecular alignment.

Radial Egg White Hydrogel Releasing Extracellular Vesicles for Cell Fate Guidance and Accelerated Diabetic Skin Regeneration.

Topology and bioactive molecules are crucial for stimulating cellular and tissue functions. To regulate the chronic wound microenvironment, mono-assembly technology is employed to fabricate a radial egg white hydrogel loaded with lyophilized adipose tissue-extracellular vesicles (radial EWH@L-EVs). The radial architecture not only significantly modified the gene expression of functional cells, but also achieved directional and controlled release kinetics of L-EVs. Through the synergy of topographical and inherent bioactive cues, radial EWH@L-EVs effectively reduced intracellular oxidative stressand promoted the polarization of macrophages toward an anti-inflammatory phenotype during the inflammatory phase. Afterward, radial EWH@L-EVs facilitated the centripetal migration and proliferation of fibroblasts and endothelial cells as the wound transitioned to the proliferative phase. During the latter remodeling phase, radial EWH@L-EVs accelerated the regeneration of granulation tissue, angiogenesis, and collagen deposition, thereby promoting the reorganization chronic wound. Compared with the gold standard collagen scaffold, radial EWH@L-EVs actively accommodated the microenvironment via various functions throughout all stages of diabetic wound healing. This can be attributed to the orientation of topological structures and bioactive molecules, which should be considered of utmost importance in tissue engineering.

High-Pressure CO2 and CH4 Transport in Smooth Crystalline Silica Mesopores: A Molecular Dynamics Study.

In this study, we use molecular dynamics (MD) simulation to study pressure-driven CO2 and CH4 flows and their slippage behaviors in β-cristobalite mesopores. The result illustrates that both CO2 and CH4 have an apparent adsorption layer on pore surface. However, significant differences in gas slippage are observed: CH4 flow shows considerable slippage, while it is negligible for CO2 flow. This disparity is attributed to the collective effect of gas molecular configurations and surface structure. The linear molecular structure of CO2 allows it to align perpendicular to the surface, even penetrating into the surface. Notably, the perpendicular orientation of CO2 molecules is energetically favored near the center of the equilateral triangle formed by adjacent oxygen atoms on β-cristobalite surface. Conversely, the symmetric molecular structure of CH4, coupled with its larger size, prevents its penetration into pore surfaces. Therefore, despite smooth crystalline surfaces, CO2 topological accessible plane is much more curved than that of CH4. Consequently, CO2 displays hesitating motions undergoing rotational movements, which significantly hinders its slippage. This study highlights the collective influences of gas molecular characteristics and surface structure on gas slippage, affording important insights into gas sequestration and the development of functional materials for gas separation.