Packing Behavior Research Articles

Discrete Element Analysis of Shape Effect on the Shear Behaviors of Ballast

Railway ballast layer is an indispensable component of railway transport. Ballast morphology plays an important effect in ballast-sleeper interaction and the durability of ballast layer. In this study, four types of ballast with different morphological parameters were generated and discrete element method was adopted to investigate the direct shear behaviors. The initial packing states were studied by analyzing the porosities and the normal contact force distributions. The shear results were verified by the reported testing results. On the other hand, one-way ANOVA tests were performed to explore the impact of ballast shape on the initial packing behaviors and the direct shear performance. Results indicated that for all four parameters, aspect ratio (AR), sphericity (Φ), roundness (RD) and convexity (CON), the initial porosities decreased first and increased subsequently along with the increase of the parameters. The four parameters could significantly affect the internal friction inside the assemblies. For each parameter, the larger the parameter, the insignificant the internal friction effect. One-way ANOVA tests revealed that all the four parameters were significant in affecting the initial porosities and the internal friction. Moreover, during the direct shear process, the larger the AR or Φ, the smaller the coordination number, which was mainly ascribed to the ballast shapes.

Discrete element simulations of flexible ribbon-like particles

A flexible ribbon-like particle model is developed based on the Discrete Element Method (DEM) for numerical modelling of biomass materials and many other flexible materials encountered in industries. In the model, a thin, irregular-shaped particle is discretized into triangular facet elements that can deform subject to internal and external forces. A library of particle templates of various shapes is established for numerical generation of a collection of particles with a statistical distribution of particle shapes in the simulations. The developed particle model is adopted to simulate uniaxial compression of biomass materials. With the calibrated model parameters, simulation results of various biomass materials and their mixtures are in good agreement with experimental data. For a better understanding of packing behavior of the biomass materials, DEM studies are performed to reveal the effects of initial particle configuration, particle shape distribution, and particle size distribution on macroscopic and micro-structural properties.

Near-Infrared II Semiconducting Polymer Dots: Chain Packing Modulation and High-Contrast Vascular Imaging in Deep Tissues.

Fluorescence imaging in the second near-infrared (NIR-II) window has attracted considerable interest in investigations of vascular structure and angiogenesis, providing valuable information for the precise diagnosis of early stage diseases. However, it remains challenging to image small blood vessels in deep tissues because of the strong photon scattering and low fluorescence brightness of the fluorophores. Here, we describe our combined efforts in both fluorescent probe design and image algorithm development for high-contrast vascular imaging in deep turbid tissues such as mouse and rat brains with intact skull. First, we use a polymer blending strategy to modulate the chain packing behavior of the large, rigid, NIR-II semiconducting polymers to produce compact and bright polymer dots (Pdots), a prerequisite for in vivo fluorescence imaging of small blood vessels. We further developed a robust Hessian matrix method to enhance the image contrast of vascular structures, particularly the small and weakly fluorescent vessels. The enhanced vascular images obtained in whole-body mouse imaging exhibit more than an order of magnitude improvement in the signal-to-background ratio (SBR) as compared to the original images. Taking advantage of the bright Pdots and Hessian matrix method, we finally performed through-skull NIR-II fluorescence imaging and obtained a high-contrast cerebral vasculature in both mouse and rat models bearing brain tumors. This study in Pdot probe development and imaging algorithm enhancement provides a promising approach for NIR-II fluorescence vascular imaging of deep turbid tissues.

Impact of dispersion conditions and coacervation on fibril formation in gellan gum-potato protein mixtures

The development of plant-based meat analogs as sustainable alternatives to traditional meat products is a major focus of the modern food industry. Meat-like structures and textures can be fabricated from protein-polysaccharide mixtures using soft matter physics approaches. In this study, we investigated the effects of gellan gum dissolution properties on the fiber formation and textural properties of potato protein-gellan gum composites. We hypothesized that the fibrous structures naturally formed by powdered gellan gum when it is dispersed in water may be useful for creating meat analogs. Zeta-potential measurements showed that cationic potato protein and anionic gellan gum formed electrostatic complexes. In the presence of excess protein, complexation of gellan gum and potato protein resulted in the formation of fibrous structures. Fiber formation and thermal gelation of the protein-polysaccharide composites depended on whether salt (100 mM NaCl) was added, and whether it was added before or after the gellan gum. The shear modulus of heat-set composite gels was higher in the presence of salt than in its absence, which was the opposite to what was observed for pure gellan gum gels. Moreover, adding salt before the gellan gum led to stronger heat set gels than adding it after the gellan gum. These effects were mainly attributed to the ability of the mineral ions to screen the electrostatic interactions between the biopolymer molecules, thereby altering their packing behavior. Our findings suggest that controlling the dispersion and coacervation of gellan gum and potato protein can be used to create fibrous structures, which may facilitate the development of plant-based meat products with improved textural attributes.

Grain-scale modeling of shear responses of dilative granular packings under stress path pertinent to rainfall-induced slope failures

Slope failures frequently occur under storm rainfall, for which the constant shear drained (CSD) stress path is more pertinent to the soil element underneath the slope surface. Soil mass in man-made slopes or other compacted slopes is often at medium-dense or even dense state. Evaluating the stability of such slopes entails a comprehensive understanding of the behavior of dilative granular packings under the CSD stress path. Here we use a robust grain-scale model to simulate responses of dilative granular packings along the CSD, constant-volume (CDCV), and conventional drained (CD) stress paths. We show that the behavior under the CSD stress path complies with the critical state theory at both macro- and micro-scale. When the second-order work becomes nonpositive, a substantial plastic strain starts to develop under the CSD loading, while a significant drop of shear strength happens along the CDCV stress path for medium-dense packing and along the CD stress path for dense packings. In these conditions, the second-order work vanishes at an almost identical stress ratio which marks the onset of strength reduction or large deformation, and such stress ratio is well correlated with the initial state parameter of the granular packing. Furthermore, we show that the CSD stress path drives an intensified fabric anisotropy and there exists a quantitative correlation between anisotropy parameters and mobilized shear strength.

Chemical topology molecular engineering of CO2-philic membranes toward highly efficient carbon capture

Membrane gas separation processes represent a crucial platform for achieving carbon neutral climate goals. CO2-philic membranes offer excellent solubility selectivity due to their high affinity, thereby allowing the separation of gas fractions with similar molecular sizes or smaller than CO2 molecules. This level of separation is difficult to achieve with conventional diffusion-dominated separation membranes. However, the gas permeability of PEO membranes is often hampered by dense chain packing and crystallization behavior. To overcome this challenge, we employed a molecular engineering approach to develop a unique PEO membrane with a hyperbranched chemical topology connection. The packing density of the polymer chains was effectively regulated by employing cross-linker molecules with distinct spatial configurations, while the free volume fraction was successfully reinforced. This unique molecular engineering strategy led to the creation of a PEO membrane exhibiting superior performance that surpassed the limit of the 2019 upper-bound line. This work demonstrated a molecular design strategy for the precise control of structural attributes in crosslinked PEO networks, offering an alternative solution for developing CO2 capture membranes and enabling further opportunities for rational membrane material design.

Heterogeneous swelling of couscous particles exposed to a high relative humidity air, as revealed by TD-NMR and X-ray tomography

The mechanical behaviour of hygroscopic granular materials is highly influenced by water. The strong dependence of individual particle properties on moisture content affects the response of their packings, which can agglomerate and eventually lead to loss of product functionality. Despite the frequent occurrence of this problem in industry, only few studies tried to explore the underlying phenomena and investigate the fundamental connection between particle and packing behaviour. This work presents an experimental study that aims to link the water uptake to the microstructural changes in assemblies of couscous, a material selected to be representative of hygroscopic granular materials. In the experiments, the samples are exposed to high relative humidity (RH), and the moisture content increase is quantified with TD-NMR, along with the shift in molecular mobility. An analogous test is performed, during which x-ray tomographies are acquired continuously. We analyse the volumetric response of the sample and of thousands of particles. Despite the oversupply of water molecules available to saturate the system, the formation of a swelling heterogeneity is observed, which we attribute to the pressure gradient affecting locally the adsorption kinetics. Combining the results obtained from the two techniques, water uptake and particle swelling are found to be linearly correlated.

Modelling of gas-solid heat transfer and pressure drop in a rock-packed bed using pore-scale simulations

The aim of this work is to provide closure laws for a macroscopic model of the heat and momentum transfer of real rock packings. We use X-ray nanotomography to obtain the geometry of two real rock packings (basalt and gravel). To address preferential flow paths on non-periodic REV, we have developed a method to properly extract closure laws on non-periodic REV from thermally fully developed pore-scale flow simulations. Several pore-scale simulations are performed over a range of Reynolds numbers (5–243) with a Prandtl number of 0.7. Then there are proposals for closure laws for real rocks, which are of completely arbitrary shape. These laws are based on a Nusselt number correlation and a dimensionless drag force correlation extracted from the pore scale simulations. The Nusselt number correlation is an extension for arbitrary shapes, i.e. real rocks, of the one proposed by Sun et al. (2015). The dimensionless drag force correlation is an original expression in excellent agreement with the experimental datas of Allen et al. (2013). The results support the hypothesis that the mean Sauter diameter is a key parameter that captures the similar behaviour of real rock packings, either for heat or momentum transfer. As this parameter cannot be replaced by other characteristic lengths in the closure laws, it needs to be properly evaluated, for example using nanotomography. For optimising the design of real rock-packed beds, the proposed closure laws allow accurate upscaling of heat transfer and pressure losses.

High-Performance Organic Solar Cells Containing Pyrido[2,3-b]quinoxaline-Core-Based Small-Molecule Acceptors with Optimized Orbit Overlap Lengths and Molecular Packing.

The central core in A-DA1 D-A-type small-molecule acceptor (SMAs) plays an important role in determining the efficiency of organic solar cells (OSCs), while the principles governing the efficient design of SMAs remain elusive. Herein, we developed a series of SMAs with pyrido[2,3-b]quinoxaline (PyQx) as new electron-deficient unit by combining with the cascade-chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. The introduction of chlorine atoms reduces the intramolecular charge transfer effects but elevates the LUMO values. Density functional theory (DFT) reveals that Py2 with ortho chlorine substituted PyQx and Py5 with two chlorine atoms yield larger dipole moments and smaller π⋅⋅⋅π stacking distances, as compared with the other three acceptors. Moreover, Py2 shows the strongest light absorption capability induced by extended orbit overlap lengths and more efficient packing structures in the dimers. These features endow the best device performance of Py2 due to the better molecular packing and aggregation behaviors, more suitable domain sizes with better exciton dissociation and charge recombination. This study highlights the significance of incorporating large dipole moments, small π⋅⋅⋅π stacking distances and extended orbit overlap lengths in dimers into the development of high-performance SMAs, providing insight into the design of efficient A-DA1 D-A-type SMAs for OSCs.

High‐Performance Organic Solar Cells Containing Pyrido[2,3‐b]quinoxaline‐Core‐Based Small‐Molecule Acceptors with Optimized Orbit Overlap Lengths and Molecular Packing

AbstractThe central core in A‐DA1D‐A‐type small‐molecule acceptor (SMAs) plays an important role in determining the efficiency of organic solar cells (OSCs), while the principles governing the efficient design of SMAs remain elusive. Herein, we developed a series of SMAs with pyrido[2,3‐b]quinoxaline (PyQx) as new electron‐deficient unit by combining with the cascade‐chlorination strategy, namely Py1, Py2, Py3, Py4 and Py5. The introduction of chlorine atoms reduces the intramolecular charge transfer effects but elevates the LUMO values. Density functional theory (DFT) reveals that Py2 with ortho chlorine substituted PyQx and Py5 with two chlorine atoms yield larger dipole moments and smaller π⋅⋅⋅π stacking distances, as compared with the other three acceptors. Moreover, Py2 shows the strongest light absorption capability induced by extended orbit overlap lengths and more efficient packing structures in the dimers. These features endow the best device performance of Py2 due to the better molecular packing and aggregation behaviors, more suitable domain sizes with better exciton dissociation and charge recombination. This study highlights the significance of incorporating large dipole moments, small π⋅⋅⋅π stacking distances and extended orbit overlap lengths in dimers into the development of high‐performance SMAs, providing insight into the design of efficient A‐DA1D‐A‐type SMAs for OSCs.

Multidimensional modelling and designing of efficient small molecule acceptors for organic solar cells

Chemical structural engineering is a helpful method to design the semi-conductors for organic solar cells (OSCs). The understanding of structural and electronic properties of materials is essential for designing and calibration of materials. By making structural adjustments at the terminal position, new small molecule acceptors can be created. Electronic properties are studied in detail. Electrostatic potential both in qualitative and quantitative way is studied to explore the electron density distribution. The electron density is significantly changed on the change of terminal groups. The excited state behaviour has also undergone a noticeable alteration. The increase in electron-deficient character at the terminal location causes the absorption spectra to shift to the red. The structural changes have an important effect on non-covalent interactions also. Through molecular dynamics (MD) simulations, the bulk behaviour of pure small molecule acceptors and their blend with polymer donor PM6 is examined. Radial distribution function is attained from MD simulations. The alteration in terminal groups has significantly changed the packing behavior of pristine acceptors and their blend with polymer donor.

Polygonal concave wear and irregular packing behavior of grinding balls for vertical grinding mill

Grinding balls are an indispensable grinding medium in vertical grinding mills, grinding ore powder to target size. Some were severely worn and unrounded by iron ore from Anshan, China, during grinding operation in the vertical grinding mill (VTM-1500, Metso Outotec). Their service failure behavior was explored, based on classifying the wear shapes of the recovered grinding balls, combined with the ore-media operating behavior. The wear mechanism of the unroundness, invagination and the special-shaped reduction was verified by the three-dimensional (3D) wear sizes and position relationships of grinding balls. The main wear model of grinding balls was polygon wear, including pentagon shape and quadrangle shape. The minor wear form was abnormal wear, containing biconvex spindle contour wear and single pit contour wear induced by free wear distribution. Both mainly occurred on the packing protective surfaces, resulting in several normalized final shapes along with the wear progress. This investigation provides a theoretical basis for understanding the interaction behavior among slurry and grinding balls.

Interplay between the Pore Network Modifications and Dynamics of Confined Polyethyleneimine in Self-Assembled Polyethyleneimine–Silica Nanoparticle Microspheres

The CO2 adsorption performance of porous materials loaded with an amine-bearing functionality is determined by the pore network of porous adsorbents and the dynamics of the adsorbed polymeric chains bearing the amine functionality. Herein, we report the modifications in the pore network of evaporation-induced self-assembled microspheres of silica nanoparticles with varying loadings of polyethyleneimine (PEI) using positron annihilation lifetime spectroscopy (PALS) and small-angle X-ray scattering (SAXS). The dynamics of the loaded PEI in the pore network of microspheres have been investigated using temperature-dependent broadband dielectric spectroscopy. PALS investigation confirms microporosity at two different length scales available at the interparticle regions in pristine silica nanoparticle-based microspheres. With PEI loading through the self-assembly process, the pore size and pore volume accessed by PALS are observed to increase up to 20 wt % loading, followed by a decrease due to modification in the clustering behavior of nanoparticles and filling of pores with excess PEI. These variations are highly consistent with the nonmonotonic jamming of silica nanoparticles, as observed from SAXS analysis, arising due to complex interactions between silica nanoparticles and PEI. Both the segmental and localized relaxations of the adsorbed PEI are observed to slow down compared to bulk PEI due to the interactions with silica nanoparticles akin to polymer nanocomposites. The slowing down of the relaxations is consistent with the free-volume variations of the confined PEI determined using PALS. The segmental relaxation time of the loaded PEI in the microspheres varies nonmonotonically with the PEI content. The observations from complementary investigations unequivocally confirm that the packing behavior of silica nanoparticles in the evaporation-induced self-assembled microspheres is controlled by the PEI content. On the other hand, the dynamics of PEI confined within the pore network of the microsphere are determined by the clustering behavior of silica nanoparticles.

High-performing anion exchange membranes enabled by diversifying the polymer backbone of quaternized poly(arylene alkylene)s

Anion-conducting poly(arylene alkylene)s are one of the most encouraging anion exchange membrane candidates with high alkaline stability for clean energy power generation. However, optimization of their conductivities often relies on the improvement of ion contents. Herein, a simple design strategy of backbone modification is reported, which can modulate the chain packing behavior and increase the free volume by introducing dimethylfluorenylene (DMeF) units into the poly(terphenylene alkylene) backbone, so as to realize the conductivity improvement of the membrane. The average chain spacing of DMeF-incorporated PTFPA membrane is extended to over 5.1 Å from the original poly(terphenylene alkylene) with the value of 4.2 Å. Accordingly, the membrane properties can be effectively modified by varying the contents of DMeF units, and PFTPA-81 containing 81 mol% of DMeF units particularly demonstrates a combination of high ion conductivity (177 mS cm−1), proper water absorption (<90 wt% at 80 °C), and uncompromised alkaline stability (>1000 h in 1 M aq. at 80 °C). Moreover, a H2–O2 fuel cell prototype fabricated from PFTPA-81 achieved a high peak power density of 1.33 W cm−2, and the cell voltage decreased less than 8% (from 0.75 V to 0.69 V) for an in-situ durability test of 30 h.

Microstructure and strength of microporous MgO refractory aggregates with nano-sized pores

ABSTRACT In this work, microporous MgO refractory aggregates with nano-sized pores were prepared by in situ decomposition method using Mg(OH)2 as raw material. The effects of firing temperatures (1600–1700°C) and compacting pressures (100–200 MPa) on the microstructures and properties of microporous MgO refractory aggregates were thoroughly studied. The results showed that the microporous MgO refractory aggregates contained two types of pore structures, which were intra-particle pores with pore sizes of 180.0–230.0 nm formed by in situ decomposition of Mg(OH)2 and inter-particle pores with pore sizes of 1.5–3.0 μm derived from particle packing between Mg(OH)2 pseudomorph particles, respectively. Besides, the firing temperatures had a great influence on the intra-particle pore size and microcrystallite size. And the compacting pressures not only influenced the intra-particle pore size via packing behaviors but also affected the inner firing behaviors of the pseudomorph particles due to the increase in H2O vapor pressure. Overall, at a compacting pressure of 150 MPa and firing temperature of 1650°C, the sample had the best comprehensive performance with a bulk density of 1.92 g/cm3, a compressive strength of 11.9 MPa, an apparent porosity of 45.0%, a relative aggregate tube strength of 25.2% and a median pore size of 262.3 nm.

Mean-field approach to random Apollonian packing.

We revisit the scaling properties of growing spheres randomly seeded in d=2,3, and 4 dimensions using a mean-field approach. We model the insertion probability without assuming a priori a functional form for the radius distribution. The functional form of the insertion probability shows an unprecedented agreement with numerical simulations in d=2,3, and 4 dimensions. We infer from the insertion probability the scaling behavior of the random Apollonian packing and its fractal dimensions. The validity of our model is assessed with sets of 256 simulations each containing 20×10^{6} spheres in two, three, and four dimensions.

The Various Packing Structures of Tb@C82 (I, II) Isomers in Their Cocrystals with Ni(OEP).

Soot-containing terbium (Tb)-embedded fullerenes were prepared by evaporation of Tb4O7-doped graphite rods in an electric arc discharge chamber. After 1,2,4-trichlorobenzene extraction of the soot and rotary evaporation of the extract, a solid product was obtained and then dissolved into toluene by ultrasonication. Through a three-stage high-pressure liquid chromatographic (HPLC) process, Tb@C82 (I, II) isomers were isolated from the toluene solution of fullerenes and metallofullerenes. With the success of the growth of cocrystals of Tb@C82 (I, II) with Ni(OEP), the molecular structures of Tb@C82 (I) and Tb@C82 (II) were confirmed to be Tb@C2v(9)-C82 and Tb@Cs(6)-C82, respectively, based on crystallographic data from X-ray single-crystal diffraction. Moreover, it was found that Tb@C82 (I, II) isomers demonstrated different packing behaviors in their cocrystals with Ni(OEP). Tb@C2v(9)-C82 forms a 1:1 cocrystal with Ni(OEP), in which Tb@C2v(9)-C82 is aligned diagonally between the Ni(OEP) bilayers to form zigzag chains. In sharp contrast, Tb@Cs(6)-C82 forms a 2:2 cocrystal with Ni(OEP), in which Tb@Cs(6)-C82 forms a centrosymmetric dimer that is aligned linearly with Ni(OEP) pairs to form one-dimensional structures in the a-c lattice plane. In addition, the distance of a Ni atom in Ni(OEP) to the Cs(6)-C82 cage is much shorter than that to the C2v(9)-C82 one, indicative of a stronger π-π interaction between Ni(OEP) and the C82 carbon cage in the cocrystal of Tb@CS(6)-C82 and Ni(OEP). Density functional theory calculations reveal that the regionally selective dimerization of Tb@CS(6)-C82 is the result of a dominant unpaired spin existing on a particular C atom of the CS(6)-C82 cage.

Linear-Shaped Low-Bandgap Asymmetric Conjugated Donor Molecule for Fabrication of Bulk Heterojunction Small-Molecule Organic Solar Cells.

A linear-shaped small organic molecule (E)-4-(5-(3,5-dimethoxy-styryl)thiophen-2-yl)-7-(5″-hexyl-[2,2':5',2″-terthiophen]-5-yl)benzo[c][1,2,5]thiadiazole (MBTR) comprising a benzothiadiazole (BTD) acceptor linked with the terminal donors bithiophene and dimethoxy vinylbenzene through a π-bridge thiophene was synthesized and analyzed. The MBTR efficiently tuned the thermal, absorption, and emission characteristics to enhance the molecular packing and aggregation behaviors in the solid state. The obtained optical bandgap of 1.86 eV and low-lying highest occupied molecular orbital (HOMO) level of -5.42 eV efficiently lowered the energy losses in the fabricated devices, thereby achieving enhanced photovoltaic performances. The optimized MBTR:PC71BM (1:2.5 w/w%) fullerene-based devices showed a maximum power conversion efficiency (PCE) of 7.05%, with an open-circuit voltage (VOC) of 0.943 V, short-circuit current density (JSC) of 12.63 mA/cm2, and fill factor (FF) of 59.2%. With the addition of 3% 1,8-diiodooctane (DIO), the PCE improved to 8.76% with a high VOC of 1.02 V, JSC of 13.78 mA/cm2, and FF of 62.3%, which are associated with improved charge transport at the donor/acceptor interfaces owing to the fibrous active layer morphology and favorable phase separation. These results demonstrate that the introduction of suitable donor/acceptor groups in molecular design and device engineering is an effective approach to enhancing the photovoltaic performances of organic solar cells.

Predicting chemoevasion potential of cancer cells from statistical chromatin packing behavior.

In malignancy, genetic, metabolic, or environmental insults may remodel chromatin structure, potentially increasing the plasticity of aberrant cell state transitions. Observed alterations to the epigenetic landscape of chromatin include gain-of-function mutations of Polycomb repressor EZH2 that block differentiation. Nucleosome remodeling and higher-order chromatin organization may also increase malignancy, with abnormalities ranging from prevalent mutations of ATP-dependent chromatin remodelers to mixing between transcriptionally active and inactive compartments. However, a universal relationship between chromatin structure and the disease state does not yet exist. Here, using the first principles of physics, we demonstrate that chromatin packing, or the statistical distribution of chromatin density in 4D, is a genome-wide regulator of phenotypic plasticity. The nucleus is a highly crowded, heterogeneous environment where DNA, RNA, proteins, and other macromolecules exert excluded volume effects, altering the kinetics and efficiency of transcription reactions. As chromatin is the major crowder in the nucleus, characterizing the chromatin mass density distribution facilitates a more complete understanding of transcription processes in a realistic nuclear environment. Combining high-resolution chromatin scanning transmission electron microscopy (ChromSTEM) and live-cell, label-free Partial Wave Spectroscopy (PWS) along with polymer physics-based analysis, we identified the existence of spatially separable packing domains, around 80 nm in radius. We then employed our understanding of fundamental chromatin packing to build a chromatin-mediated model of transcription that incorporates two pertinent aspects of phenotypic plasticity: transcriptional malleability, the ability of a cell to upregulate certain genes within a critical time frame, and transcriptional heterogeneity, a cell population's range of functional states. Finally, we extended our transcription model to predict how the average chromatin packing behavior of a cell population contributes directly to cancer cell survival upon chemotherapy treatment. Experimental observations confirmed model predictions, underlying the importance of chromatin packing in chemoevasion processes.

Hybrid Cycloalkyl-Alkyl Chain-Based Symmetric/Asymmetric Acceptors with Optimized Crystal Packing and Interfacial Exciton Properties for Efficient Organic Solar Cells.

Hybrid cycloalkyl-alkyl side chains are considered a unique composite side-chain system for the construction of novel organic semiconductor materials. However, there is a lack of fundamental understanding of the variations in the single-crystal structures as well as the optoelectronic and energetic properties generated by the introduction of hybrid side chains in electron acceptors. Herein, symmetric/asymmetric acceptors (Y-C10ch and A-C10ch) bearing bilateral and unilateral 10-cyclohexyldecyl are designed, synthesized, and compared with the symmetric acceptor 2,2'-((2Z,2'Z)-((12,13-bis(2-butyloctyl)-3,9 bis(ethylhexyl)-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3″':4',5']thieno[2',3':4,5] pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10- diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (L8-BO). The stepwise introduction of 10-cyclohexyldecyl side chains decreases the optical bandgap, deepens the energy level, and enables the acceptor molecules to pack closely in a regular manner. Crystallographic analysis demonstrates that the 10-cyclohexyldecyl chain endows the acceptor with a more planar skeleton and enforces more compact 3D network packing, resulting in an active layer with higher domain purity. Moreover, the 10-cyclohexyldecyl chain affects the donor/acceptor interfacial energetics and accelerates exciton dissociation, enabling a power conversion efficiency (PCE) of >18% in the 2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3″':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (Y6) (PM6):A-C10ch-based organic solar cells (OSCs). Importantly, the incorporation of Y-C10ch as the third component of the PM6:L8-BO blend results in a higher PCE of 19.1%. The superior molecular packing behavior of the 10-cyclohexyldecyl side chain is highlighted here for the fabrication of high-performance OSCs.