Medium-range Order Research Articles

Structural Aspects of Ambient-Temperature Densification of Highly Crack-Resistant Borosilicate and Aluminoborosilicate Glasses: Two Case Studies Examined by Solid-State NMR.

The structural aspects of ambient-temperature densification via pressurization at 25 GPa were studied by solid-state NMR for two case studies: An alkaline earth boroaluminosilicate glass with the composition 6CaO-3SrO-1BaO-10Al2O3-10B2O3-70SiO2 (labeled SAB) and a sodium magnesium borosilicate glass with the composition 10Na2O-10MgO-20B2O3-60SiO2 (labeled MNBS). For SAB glass, cold pressurization results in significant increases in the average coordination numbers of both boron and aluminum, in line with previous results found in hot-compressed alkali aluminoborosilicate glasses. In addition, 27Al/11B dipolar recoupling experiments reveal a significant decrease in the 11B/27Al dipolar interaction strength upon pressurization, suggesting that the higher-coordinated boron and aluminum species experience weaker magnetic interactions. While this is an expected consequence of the longer internuclear distances involving higher coordination states, the magnitude of the effect also is consistent with a decrease of average B-O-Al internuclear connectivity. By conjecture, a decreased B-O-Al connectivity may present a mechanism of plastic flow inhibiting crack initiation in aluminoborosilicate glasses. In the case of the MNBS glass, no change in the average boron coordination number was observed within experimental error; however, densification increases the extent of B-O-Si connectivity at the expense of small ring structures with dominant B-O-B connectivity. With regard to boron coordination, the data obtained for both case studies differ from those previously found in a series of alkali borosilicate glasses, which had shown an unexpected decrease in N4 upon increased pressure. The results of the present study highlight the importance of changes of medium-range order regarding densification.

Electron conduction mechanism in indium oxide and its implications for amorphous transport

The electron conduction mechanism in indium oxide (In2O3) and its implications for amorphous transport have been investigated from an orbital overlap perspective. Combined density functional theory and empirical tight binding modeling reveal that the electron transport is facilitated by the neighboring metal atomic s orbital overlap “without” oxygen’s p-orbital involvement. In other words, the electron transport pathway in oxides is only due to the metal-metal medium range connection. This electron conduction mechanism is extended to amorphous In2O3 which unveils that the amorphous disorder influences the electron transport through impacting the metal-metal medium range order including metal-metal coordination number and metal-metal separation. Our results provide an insight into the current theoretical understanding of electron transport in amorphous oxide semiconductors.

Static and dynamic disorder in ion-implanted silica glass

Structural disorder in solid-state materials has a direct impact on the complex of its physicochemical properties and functional characteristics of developed devices. The purpose of this work is to establish the influence of ion irradiation of SiO2 glass on static and dynamic disorder separately. Silica glasses implanted with carbon ions were studied using optical absorption spectroscopy and Raman spectroscopy. The temperature behavior of the fundamental absorption edge was considered in terms of the Urbach rule. The dose dependences of the root-mean-square atomic displacements caused by static and dynamic disorder were obtained. Analysis of Raman spectra confirmed the optical spectroscopy data and revealed a decrease in the medium-range order size along with topological changes in the SiO2 structure after ion implantation. The described step-by-step technique for quantitatively assessing the degree of static and dynamic disorder is universal and can be used to analyze other materials.

Medium-range order structure analysis of metallic glasses based on reverse Monte Carlo modeling

The elucidation of amorphous alloy characteristics presents a formidable challenge due to the absence of crystalline arrangements and enigmatic imperfections. This study aimed to tackle this challenge through a comprehensive investigation utilizing synchrotron X-ray diffraction (XRD), extended X-ray absorption fine structure spectroscopy (EXAFS), ab initio molecular dynamics (AIMD) simulations, and reverse Monte Carlo (RMC) modeling. The primary objective was to delve into the medium range order (MRO) structure of metallic glasses (MGs) containing CuXZr100-X, wherein X represents values of 50, 56, 60, and 64. The results obtained from this research demonstrate that an increase in the Cu atom concentration within Cu-Zr MGs leads to the formation of complete icosahedral clusters and high-coordination polyhedral connections, thereby bolstering the stability and heterogeneity of local structures. Examination of the stiff full icosahedral bones shows that defects exist in the network connections on the MRO, resulting in a lack of connectivity in the positive icosahedron. Conversely, the density of defects decreases with an increase in Cu content. The observation suggests that the observed low MRO defects in Cu64Zr36 MGs may be accountable for their excellent glass-forming ability and kinetic stability.

Comprehensive characterization of the structure of Zr-based metallic glasses

Structure of metallic glasses fascinates as the generic amorphous structural template for ubiquitous systems. Its specification necessitates determination of the complete hierarchical structure, starting from short-range-order (SRO) → medium-range-order (MRO) → bulk structure and free volume (FV) distribution. This link has largely remained elusive since previous investigations adopted one-technique-at-a-time approach, focusing on limited aspects of any one domain. Reconstruction of structure from experimental data inversion is non-unique for many of these techniques. As a result, complete and precise structural understanding of glass has not emerged yet. In this work, we demonstrate the first experimental pathway for reconstruction of the integrated structure, for Zr67Ni33\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ ext{Zr}}_{{{67}}} {\ ext{Ni}}_{{{33}}}$$\\end{document} and Zr52Ti6Al10Cu18Ni14\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ ext{Zr}}_{{{52}}} {\ ext{Ti}}_{{6}} {\ ext{Al}}_{{{10}}} {\ ext{Cu}}_{{{18}}} {\ ext{Ni}}_{{{14}}}$$\\end{document} glasses. Our strategy engages diverse (× 7) multi-scale techniques [XAFS, 3D-APT, ABED/NBED, FEM, XRD, PAS, FHREM] on the same glass. This strategy complemented mutual limitations of techniques and corroborated common parameters to generate complete, self-consistent and precise parameters. Further, MRO domain size and inter-void separation were correlated to identify the presence of FV at MRO boundaries. This enabled the first experimental reconstruction of hierarchical subset: SRO → MRO → FV → bulk structure. The first ever image of intermediate region between MRO domains emerged from this link. We clarify that determination of all subsets is not our objective; the essence and novelty of this work lies in directing the pathway towards finite solution, in the most logical and unambiguous way.

Liquid-Liquid Crossover in Water Model: Local Structure vs Kinetics of Hydrogen Bonds.

In equilibrium and supercooled liquids, polymorphism is manifested by thermodynamic regions defined in the phase diagram, which are predominantly of different short- and medium-range order (local structure). It is found that on the phase diagram of the water model, the thermodynamic region corresponding to the equilibrium liquid phase is divided by a line of the smooth liquid-liquid crossover. In the case of the water model TIP4P/2005, this crossover is revealed by various local order parameters and corresponds to pressures on the order of 3150 ± 350 atm at ambient temperature. In the vicinity of the crossover, the dynamics of water molecules change significantly, which is reflected, in particular, in the fact that the self-diffusion coefficient reaches its maximum values. In addition, changes in the structure also manifest themselves in changes in the kinetics of hydrogen bonding, which are captured by values of such quantities as the average lifetime of hydrogen bonding, the average lifetimes of different local coordination numbers, and the frequencies of changes in different local coordination numbers. An interpretation of the hydrogen bond kinetics in terms of the free energy landscape concept in the space of possible coordination numbers is proposed.

Investigating the influence of medium range order defects on shear instability in Cu64Zr36 metallic glass

The occurrence of shear instability in metallic glasses is profoundly influenced by the spatial perturbation of material properties. Despite the considerable research on the origin of shear transformation zones (STZ), it remains a challenge to understand the behavior from a structural perspective. In this study, extensive molecular simulations (MD) and synchrotron diffraction were employed to characterize the structural features of medium-range order (MRO) defects in Cu64Zr36 metallic glass. These defects manifest as line-like interruptions in the connections between full icosahedral clusters. And it was also observed that the size and content of these defects are closely related to the history of the glass formation process. Moreover, we explored the contribution of these MRO defects, which are comparable in size to the STZ, in the genesis of shear instability. We uncovered that a large strain gradient exists in these regions under external loads, providing a convenient pathway for STZ activation. Notably, the generation of MRO defects are also going on as the STZ evolves. These insightful findings provide valuable insights and offer a promising avenue for the design and development of advanced metallic glass materials with enhanced structural integrity.

Medium-range structural order in amorphous Ge2Sb2Te5 phase change material

The crystallization rate is an important factor for the application of phase change materials as memory devices, which, thus, motivates a strong interest in the underlying crystallization processes. We analyzed the crystallization kinetics of as-deposited amorphous Ge2Sb2Te5 by differential scanning calorimetry, revealing that the thermal treatment below the crystallization onset temperature effectively enhances the crystallization rate compared to the as-deposited samples. Variable resolution fluctuation electron microscopy was carried out to characterize the corresponding amorphous structure of the as-deposited films and the differently annealed states regarding their medium-range order (MRO). As a result, relatively large MRO correlation lengths in the range of 3–4 nm were observed, whereas the MRO volume fraction doubled after longer annealing treatments, demonstrating the importance of MRO and MRO tuning for optimizing the properties of amorphous phase change materials. The increased volume fraction of the MRO seems to also favor an increased nanoindentation hardness.

Medium-range imperfect order determining the slow β-relaxation in metallic glasses

Medium-range imperfect order determining the slow β-relaxation in metallic glasses

Discontinuous phase diagram of amorphous carbons.

The short-range order and medium-range order of amorphous carbons demonstrated in experiments allow us to rethink whether there exist intrinsic properties hidden by atomic disordering. Here we presented six representative phases of amorphous carbons (0.1-3.4g/cm3), namely, disordered graphene network (DGN), high-density amorphous carbon (HDAC), amorphous diaphite (a-DG), amorphous diamond (a-D), paracrystalline diamond (p-D), and nano-polycrystalline diamond (NPD), respectively, classified by their topological features and microstructural characterizations that are comparable with experiments. To achieve a comprehensive physical landscape for amorphous carbons, a phase diagram was plotted in the sp3/sp2 versus density plane, in which the counterintuitive discontinuity originates from the inherent difference in topological microstructures, further guiding us to discover a variety of phase transitions among different amorphous carbons. Intriguingly, the power law, log(sp3/sp2) ∝ ρn, hints at intrinsic topology and hidden order in amorphous carbons, providing an insightful perspective to reacquaint atomic disorder in non-crystalline carbons.

Atomic-scale structures determining the plasticity of metallic glasses viewed from the icosahedral medium-range orders and its spatial distribution

In the study of metallic glasses, the characterization of free volumes and icosahedral clusters has been a longstanding approach to understanding plasticity. However, recent research has illuminated the limitations of exclusively relying on these factors to explain the plastic deformation of metallic glasses. To address this limitation, we have introduced the concept called the h-value in a prior study, which quantifies the spatial distribution of disrupted interpenetrating connections of icosahedra and provides insights into how minor elements influence the deformation behavior of metallic glasses. However, the h-value was only employed on Cu50Zr50, Cu47.5Zr47.5Al5, and (Cu0.5Zr0.5)100-xAgx alloys and provided insight into the correlation between the spatial distribution of icosahedra and plasticity, but it is needed to be validated on a wider range of alloys to confirm the applicability of the h-value. In this study, we utilize a Cu–Zr binary amorphous system, known for its compositional diversity and corresponding wide range of plasticity, to validate and benchmark our approach against experimental results. Our findings underscore the robustness of the h-value as a structural descriptor, representing the degree of spatial distribution within the local structural basis. This metric holds promise as a valuable tool for determining the plasticity of metallic glasses.

Four-Dimensional Scanning Transmission Electron Microscopy: Part II, Crystal Orientation and Phase, Short and Medium Range Order, and Electromagnetic Fields

Abstract Four-dimensional scanning transmission electron microscopy (4D-STEM) is a spatially resolved electron diffraction technique that records the electron scattering distribution at each point of the electron beam raster, thereby producing a four-dimensional dataset. This second installment of this series presents applications of 4D-STEM, including measurements of crystal orientation and phase, short- and medium-range order, and internal electromagnetic fields.

Superior mechanical properties of a Zr-based bulk metallic glass via laser powder bed fusion process control

Additive manufacturing has made the fabrication of large-dimensioned bulk metallic glasses (BMGs) achievable; however, questions remain regarding how to control the processing parameters to obtain dense and fully amorphous BMGs with desirable mechanical properties. Here, laser powder bed fusion (LPBF) was used to produce dense and fully amorphous Zr59.3Cu28.8Nb1.5Al10.4 BMG samples from two different starting powders within a large processing window of laser powers and scanning speeds. X-ray diffraction (XRD) revealed that fully amorphous XRD patterns were obtained for samples with high relative densities (>99 %) when the LPBF energy density ranged from ∼20 J/mm3 up to ∼33 J/mm3 for coarse powder with low oxygen and up to ∼30 J/mm3 for fine powder with higher oxygen. For the fully XRD amorphous samples, strength and hardness increased with increasing energy density while the relaxation enthalpy and ductility decreased. Transmission electron microscopy revealed that the softer samples contain larger medium range order clusters within the amorphous matrix. With higher LPBF energy density, high relative density was still achieved along with devitrification and embrittlement. While lower energy densities below ∼20 J/mm3 could retain a fully XRD amorphous structure, such samples had relative densities <99 %. When comparing the two powders, the coarse powder with four times lower oxygen content gave better glass forming ability, compression ductility up to 6 % plastic strain, and fracture toughness up to ∼38 MPa√m. These findings demonstrate that it is possible to tailor the structure and mechanical properties of BMGs by tuning the LPBF process parameters within a wide processing window.

Analysis of icosahedral structure in rapidly solidified Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; amorphous alloy under high pressure

Compared with traditional glass, metallic glass (MG) has excellent properties, such as high strength, high hardness, high fracture toughness, good soft magnetic properties and corrosion resistance due to its unique structure. Such properties enable it to be used in optics, electronics, construction and other fields, making it a highly promising new material with great application potential. As the properties of amorphous alloys are closely linked with their local structures, microstructure characteristics have always been a research focus in the amorphous field. Previous studies show that the onset temperature of heredity and the hereditary fraction of characteristic clusters can be used to effectively evaluate the glass-forming ability. In order to obtain the relationship between the microstructure characteristic and cluster evolution of amorphous alloy, and reveal the formation of glass, the glass transition processes of the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; alloy under different pressure conditions are simulated by using the molecular dynamics method, and the heredity and evolution of the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; amorphous alloy are analyzed by using the cluster-type index method and the reverse tracking method. The simulation results show that the glass transition temperature of the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; alloy can be increased when the pressure is higher, and a large number of icosahedra are formed in the solidified alloy when the pressure is sufficiently high. Icosahedron is a kind of structure that widely exists in amorphous materials and has been studied for quite a long time. In this work, a detailed comparative analysis of two icosahedra is conducted and the heritability of clusters with different chemical compositions under high pressure is studied. The results show that it is easier for icosahedra with central atom Pd and those with central atom Si to form a medium-range order in the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; amorphous alloy. An increase in pressure conduces to the increase of both onset temperature of heredity and hereditary fraction. Combined with the results of cluster heredity analysis at 0 GPa, the Si-centered clusters have stronger heritability than Pd-centered clusters, thus the former ones have a greater influence on the glass-forming ability. These findings are of significance in understanding the relationship between microstructure evolution and glass formation, and also providing certain guidance for designing amorphous alloys.

On the mechanism of helium permeation through silica glass

&lt;abstract&gt; &lt;p&gt;Although the densities of crystal quartz and vitreous silica differ only by about 17% (2.65 and 2.20 g/cm&lt;sup&gt;3&lt;/sup&gt;, respectively), the helium permeability of silica glass is six orders more elevated than that of crystal quartz. This vast difference has puzzled researchers for decades considering that silica glass and quartz crystal have the same chemical composition. This work discusses the mechanism of high helium permeation through silica glass. It briefly reviews the experimental data and its contradictions with the continuous random network theory. A recently proposed nanoflake model for silica glass structure is utilized to explain the origin of glass permeation to helium. According to the nanoflake model, the formation of nanoflakes not only brings a one-dimensional medium-range ordering structure into silica glass but simultaneously creates regions where van der Waals bonds replace the oxygen-silicon covalent bonds. It is the weakness of van der Waals bonds that causes the helium mobility in these areas to increase.&lt;/p&gt; &lt;/abstract&gt;

Analysis of icosahedral structure in rapidly solidified Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; amorphous alloy under high pressure

Compared with traditional glass, metallic glass (MG) has excellent properties, such as high strength, high hardness, high fracture toughness, good soft magnetic properties and corrosion resistance due to its unique structure. Such properties enable it to be used in optics, electronics, construction and other fields, making it a highly promising new material with great application potential. As the properties of amorphous alloys are closely linked with their local structures, microstructure characteristics have always been a research focus in the amorphous field. Previous studies show that the onset temperature of heredity and hereditary fraction of characteristic clusters can be used to effectively evaluate the ability of an amorphous alloy to form glass. In order to obtain the relationship between the microstructure characteristic and cluster evolution of amorphous alloy, and reveal the formation of glass, the glass transition processes of the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; alloy under different pressure conditions are simulated by using the molecular dynamics method, and the heredity and evolution of the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; amorphous alloy are analyzed by using the cluster-type index method and the reverse tracking method. The simulation results show that the glass transition temperature of the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; alloy can be increased when the pressure is higher, and a large number of icosahedra are formed in the solidified alloy when the pressure is sufficiently high. Icosahedron is a kind of structure that widely exists in amorphous materials and has been studied for quite a long time. In this work, a detailed comparative analysis on two icosahedra is conducted and the heritability of clusters with different chemical compositions under high pressure is studied. The results show that it is easier for icosahedra with central atom Pd and those with central atom Si to form a medium-range order in the Pd&lt;sub&gt;82&lt;/sub&gt;Si&lt;sub&gt;18&lt;/sub&gt; amorphous alloy. An increase in pressure conduces to the increasing of both onset temperature of heredity and hereditary fraction. Comparing with the results of cluster heredity analysis under 0 GPa, the Si-centered clusters have stronger heritability than Pd-centered clusters, thus the former ones have a greater influence on the ability to form glass. These findings are of significance in understanding the relationship between microstructure evolution and glass formation,and also providing certain guidance for designing amorphous alloys.

Temperature-Dependent Paracrystalline Nucleation in Atomically Disordered Diamonds.

Atomically disordered diamonds with medium-range order realized in recent experiments extend our knowledge of atomic disorder in materials. However, the current understanding of amorphous carbons cannot answer why paracrystalline diamond (p-D) can be formed inherently different from other tetrahedral amorphous carbons (ta-Cs), and the emergence of p-D seems to be easily hindered by inappropriate temperatures. Herein, we performed atomistic-based simulations to shed light on temperature-dependent paracrystalline nucleation in atomically disordered diamonds. Using metadynamics and two carefully designed collective variables, reversible phase transitions among different ta-Cs can be presented under different temperatures, evidenced by corresponding local minima on the free energy surface and reaction path along the free energy gradient. We found that p-D is preferred in a narrow range of temperatures, which is comparable to real experimental temperatures under the Arrhenius framework. The insights and related methods should open up a perspective for investigating other amorphous carbons.

Solution-Processed Non-Crystalline Solid Electrolytes for Advanced Energy Storage

Advanced batteries containing a Li metal anode (LMA) are needed to enable the clean economy and meet ambitious climate targets. Currently, LMA batteries are limited by dendrite propagation due to the non-uniform plating and stripping of Li, which is detrimental to cell performance. The non-crystalline solid electrolyte (SE), lithium phosphorus oxynitride (LiPON) is unique in demonstrating stable Li plating/stripping at appreciable rates, but its synthesis requires costly and slow vacuum deposition methods. We use aqueous precursor solutions which are rapidly condensed during spin coating and gently annealed to produce dense, flat, Li metal oxide films without long-range order. However, such solution-processed SEs typically exhibit ionic conductivities (σ ion ) too low for energy storage applications (~10-8 S cm-1) and far lower than vacuum-deposited LiPON (~10-6 S cm-1).We will discuss various approaches to increase the σion of these materials, including compositional engineering and controlled processing conditions. Structure-property relationships have been elucidated using modelling of the local structure and interphase formation against Li evaluated by time-dependent electrochemical impedance spectroscopy and in situ X-ray photoelectron spectroscopy. Electrochemical testing of these films deposited onto a current collector in an anode-free cell will be used to evaluate their ability to facilitate stable deposition and stripping of Li.Initial exploration of processing parameters have yielded σion values > 10-7 S cm-1 [1] and the presence of medium-range order (nanocrystalline domains) in some cases. Beyond Li, new non-crystalline SEs for other ions will be discussed. As only limited chemical compositions and processing conditions of these materials have been reported, with no corresponding structural studies, our work provides insight to enable the optimisation and discovery of scalable non-crystalline SEs for advanced batteries.1. P. Vadhva, T. Gill, J. H. Cruddos, S. Said, M. Siniscalchi, S. Narayanan, M. Pasta, T.S. Miller, A.J.E. Rettie. Engineering solution-processed non-crystalline solid electrolytes for Li metal batteries. Chemistry of Materials, 2022, 35, 3, 1168–1176.

Unveiling the crystallization mechanism of cadmium selenide via molecular dynamics simulation with machine-learning-based deep potential

Cadmium selenide (CdSe) is an inorganic semiconductor with unique optical and electronic properties that make it useful in various applications, including solar cells, light-emitting diodes, and biofluorescent tagging. In order to synthesize high-quality crystals and subsequently integrate them into devices, it is crucial to understand the atomic scale crystallization mechanism of CdSe. Unfortunately, such studies are still absent in the literature. To overcome this limitation, we employed an enhanced sampling-accelerated active learning approach to construct a deep neural potential with ab initio accuracy for studying the crystallization of CdSe. Our brute-force molecular dynamics simulations revealed that a spherical-like nucleus formed spontaneously and stochastically, resulting in a stacking disordered structure where the competition between hexagonal wurtzite and cubic zinc blende polymorphs is temperature-dependent. We found that pure hexagonal crystal can only be obtained approximately above 1430 K, which is 35 K below its melting temperature. Furthermore, we observed that the solidification dynamics of Cd and Se atoms were distinct due to their different diffusion coefficients. The solidification process was initiated by lower mobile Se atoms forming tetrahedral frameworks, followed by Cd atoms occupying these tetrahedral centers and settling down until the third-shell neighbor of Se atoms sited on their lattice positions. Therefore, the medium-range ordering of Se atoms governs the crystallization process of CdSe. Our findings indicate that understanding the complex dynamical process is the key to comprehending the crystallization mechanism of compounds like CdSe, and can shed lights in the synthesis of high-quality crystals.

Topology of icosahedral network responsible for yielding in CuZr metallic glasses

Metallic glasses exhibit yielding behavior under mechanical deformation. However, the underlying atomic structural basis is still elusive. Here we investigated atomic structural evolution in both average fraction of atomic clusters and their spatial distribution for CuZr metallic glasses during deformation via molecular dynamic simulation. It is found that while the icosahedral clusters in the initial structures of CuZr glassy samples exhibit unique mechanical response to deformation, compared to other types of atomic clusters, its fraction is not key to the yielding of metallic glasses. We further explored the spatial distribution of icosahedral clusters, i.e., icosahedral medium-range order by analyzing the network formed via their interpenetrating connections. It is found that the topology of the icosahedral network plays the essential roles in the yielding of CuZr metallic glasses. Within the icosahedral networks, nodes with degree k > 1 mainly determine the yield strain, which is general in CuZr metallic glasses and independent of the fraction of icosahedral clusters. Moreover, it is also found that the larger the node degree of the interpenetrated icosahedral network is, the higher the yield strain is. Therefore, the disruption of the icosahedral network corresponds to the yielding of metallic glasses. The roles of nodes with degree k = 0 and 1 in the yielding were also elucidated. In addition, the newly formed icosahedral clusters during deformation are found to have almost no impact on the yielding of metallic glasses. Our findings establish a quantitative relation between atomic structures and yielding in CuZr metallic glasses based on the perspective of structural topology, and may shed light on the deformation mechanism of amorphous solids.