Structure Of Clusters Research Articles

Atomic-level design of biomimetic iron-sulfur clusters for biocatalysis.

Designing biomimetic materials with high activity and customized biological functions by mimicking the central structure of biomolecules has become an important avenue for the development of medical materials. As an essential electron carrier, the iron-sulfur (Fe-S) clusters have the advantages of simple structure and high electron transport capacity. To rationally design and accurately construct functional materials, it is crucial to clarify the electronic structure and conformational relationships of Fe-S clusters. However, due to the complex catalytic mechanism and synthetic process in vitro, it is hard to reveal the structure-activity relationship of Fe-S clusters accurately. This review introduces the main structural types of Fe-S clusters and their catalytic mechanisms first. Then, several typical structural design strategies of biomimetic Fe-S clusters are systematically introduced. Furthermore, the development of Fe-S clusters in the biocatalytic field is enumerated, including tumor treatment, antibacterial, virus inhibition and plant photoprotection. Finally, the problems and development directions of Fe-S clusters are summarized. This review aims to guide people to accurately understand and regulate the electronic structure of Fe-S at the atomic level, which is of great significance for designing biomimetic materials with specific functions and expanding their applications in biocatalysis.

Wood trade regions of Russia: clustering approach development

Network analysis of the Russian timber industry was based on the information about timber transactions between Russian companies in 2020. The data were collected from the Unified State Automated Information System Accounting Timber and Transactions with It. The method of graph clustering was developed. The first step is clustering of the hole graph by Leiden algorithm. The second step is drawing of each Leiden created cluster in abstract space using Fruchterman–Reingold layout and extraction of clusters from layout using meanshift algorithm. Such approach helped us to divide many Leiden-created clusters into components. This algorithm has a problem of resolution limit. It tends to combine some medium and small clusters into large ones. Also, a special method was developed to limit the uncertainty of clustering – both Leiden algorithm and Fruchterman–Reingold layout are non-deterministic algorithms. Wood trade clusters vary in size and content. They are rather autonomous. The average share of intra-cluster trade is 89%. The modularity score of our partition is 0.863. Each cluster has been described using open sources from the Internet. The content of the clusters does not contradict the logic of the wood industry processes. The clusters create rather compact areas on the map – wood trade regions. Their borders often overlap with existing administrative boundaries. Five types of network structure of clusters were defined: vertical monocentric, vertical polycentric, horizontal, dendritic, simple. There are three factors of clustering in wood industry of Russia: production chains (4 types – pulp, plywood, lumber, chipboard chains), demand chains (redistribution of raw material between manufacturers within the cluster, accumulation of wood volumes for some enterprises outside the cluster, wood trade between traders within the cluster), common holder. We have shown that existing approaches to cluster detection based on location quotients often misrepresent economic networks.

Atomically precise Cu32 nanoclusters with selenide doping: Synthesis, bonding, and catalysis

AbstractCopper nanoclusters with stable compositions and precise structures have long been sought after, as they possess properties that are absent in gold and silver counterparts. However, the creation of copper nanoclusters with novel compositions, structures, and functionalities remains largely unexplored in the literature. In this study, we demonstrate that selenide doping is an effective method for fabricating stable copper nanostructures through controlled synthesis and structure determination of a copper–selenide nanocluster. The nanocluster of [Cu32Se7(BnSe)18(PPh3)6]+ (denoted as Cu32Se7, Bn is benzyl) has been prepared by reducing copper salts in the presence of organic diselenides. The atomic structure of the Cu32Se7 cluster, accurately determined through single‐crystal X‐ray diffraction, reveals a core–shell arrangement of Cu20Se7@Cu12(BnSe)18(PPh3)6, where Se2− anions are well dispersed in the Cu20 framework. Notably, this cluster represents a rare example of copper–selenide semiconductor nanoclusters. Experimental and theoretical analysis shows strong interactions between Se ligands and metal atoms, resulting in high stability of the Cu32Se7 cluster. Furthermore, the cluster exhibits excellent catalytic performance in the hydroboration reaction of alkynes, producing a range of vinylboron compounds with adjustable structures and functions. Importantly, the cluster undergoes no structural or nuclearity changes during the reaction, as confirmed by extended X‐ray absorption fine structure and X‐ray photoelectron spectroscopy studies. This study not only presents a molecular cluster model highlighting the effectiveness of selenide dopants in fabricating new copper nanostructures but also paves the way for utilizing stable copper nanoclusters in diverse and exciting areas beyond catalysis.

Scoping review of epigenetics on neurodegenerative diseases: research frontiers and publication status.

Epigenetics has significantly evolved and emerged as important players in the pathogenesis of neurodegenerative diseases. However, a scientometric synthesis of such changes over time is currently lacking. We conducted a comprehensive search of the Web of Science Core Collection from inception until November 5, 2022, using appropriate keywords. Our primary objective was to employ scientometric analysis to depict changes in keywords over time and to assess the structure and credibility of clusters. Additionally, we examined the network of research (countries, institutions, and authors) using CiteSpace and VOSviewer. We identified 25 clusters with well-structured networks (Q = 0.82) and highly credible clustering (S = 0.91) from 16,181 articles published between 1999 and 2022. Our findings are as follows: (a) the literature and research interest concerning the epigenetics of neurodegenerative diseases are continuously growing; (b) the three most productive countries are the USA, China, and Germany; (c) international collaborative relationships exist, alongside small, isolated collaboration networks of individual institutions. The number and impact of global publications on the epigenetics of neurodegenerative diseases have expanded rapidly over the past 20 years. This review provides valuable guidelines for researchers interested in neurodegenerative diseases research.

Gravitational wave background from primordial black holes in globular clusters

Primordial black holes still represent a viable candidate for a significant fraction, if not for the totality, of dark matter. If these compact objects have masses of order tens of solar masses, their coalescence can be observed by current and future ground-based gravitational wave detectors. Therefore, finding new gravitational wave signatures associated with this dark matter candidate can either lead to their detection or help constraining their abundance. In this work we consider the phenomenology of primordial black holes in dense environments, in particular globular clusters. We model the internal structure of globular clusters in a semi-analytical fashion, and we derive the expected merger rate. We show that, if primordial black holes are present in globular clusters, their contribution to the GW background can be comparable to other well-known channels, such as early- and late-time binaries, thus enhancing the detectability prospects of primordial black holes and demonstrating that this contribution needs to be taken into account.

FRACTAL DIMENSION OF STAR CLUSTERS

Quantitative analysis of the structure of star clusters is crucial for understanding their formation and evolution. In this article, we explore the application of fractal dimension analysis to study the evolution of star clusters, also fractal dimension, a concept from fractal geometry, provides a quantitative measure of the complexity and self-similarity of geometric objects. By considering star clusters as complex networks, we employ the box covering method to calculate their fractal dimension. Our methodology combines the well-established Minimum Spanning Tree (MST) and Box-Covering (BC) methods and using these methods, the fractal structure of the clusters was determined. It was revealed that star clusters disintegrate at a fractal dimension of 1.3 and obey a power law. It should be noted that the obtained result was compared with the results of the McLuster.

Improved aggregation/agglomeration-dependent percolation theory to predict nanoparticle-aided electrical conductivity in polymer nanocomposites: A combination of analytical strategy and artificial neural network

The formation of aggregates/agglomerates in polymer nanocomposites is known as an inevitable phenomenon that may affect many physical/mechanical properties. Accordingly, in this study, the impacts of the size and content of nanoparticle clusters on the electrical conductivity of polymer matrices containing spherical nanoparticles were analytically evaluated. To this end, the well-known percolation theory was improved by involving major system parameters, affected by aggregation/agglomeration, reported to be indicative of how electricity may conduct through (e. g. tunneling effect, percolation threshold, content and equivalent electrical conductivity of nanoparticle domains, etc.). The characteristics of the aggregates/agglomerates were estimated via the combination of a devised strategy, representing the structure of clusters, and the fundamentals of the percolation theory. The average electrical conductivity and density of polymer/particle interphase, formed around nanoparticle domains were calculated using a particularly developed scaling theory. Also, the hypothetical relative location of nanoparticle domains to each other was defined by calculating the average nearest distance between them, benchmarked against the tunneling distance. A two-stage validation procedure was conducted using the data elicited from the literature in order to first, evaluate the model efficiency and secondly, assess its predictive capabilities with the aid of an artificial neural network (error < 7 %).

Cations Induced Fluorescence Enhancement in Keggin-Al13 for Quantitative Detection.

The Keggin-Al13 hydroxide clusters serve as pivotal models for elucidating molecular pathways in geochemical reactions. In this study, we presented a strategy aiming at the quantitative detection of ε-Al13 Keggin clusters using photoluminescent spectra. Specifically, we manipulate the electronic structure of ε-Al13 by introducing Na ions onto the ε-Al13 surface, encapsulated within a Na-O3 motif. The Na-ion-modified ε-Al13 (Na-ε-Al13) cluster demonstrates incredible photoluminescent qualities, with fluorescence excitation and emission peaks centered at 365 and 436 nm, respectively. In addition, the fluorescence intensities display a linear dependence on the concentrations of Na-ε-Al13, with a detection limit of 15.4 μM. This correlation facilitates the quantitative and precise determination of Na-ε-Al13 concentrations via fluorescence. Both experimental characterizations and theoretical calculations underscore the importance of decorated Na ions in regulating the electronic structure of the ε-Al13 cluster. Lastly, the influence of external anions/cations on the photoluminescent properties of ε-Al13 primarily mirrors modifications to the nonradiative decay process, which is regulated via electrostatic interactions. This work demonstrates an effective strategy for quantitative detection of the ε-Al13 Keggin clusters through photoluminescent spectra.

The Rectangular Niobium Oxyiodide Cluster Nb4OI10 – A Narrow Band‐Gap Semiconductor

AbstractA metal‐rich niobium oxyiodide was prepared by soft reduction of NbI4. The structure of the new compound Nb4OI10 was determined by single‐crystal X‐ray diffraction and contains a rectangular Nb4(μ4‐O) cluster that is interconnected into layers by iodide ligands. The local structure of the Nb4OI10 cluster bears a close relationship to a defect Nb6I11 structure. The two‐dimensional van der Waals material Nb4OI8I4/2] is a small band‐gap semiconductor (&lt;1 eV), as analysed by electrical conductivity measurements, photoresponse, experimental band gap determination, and band structure calculation.

Revealing the surface structure and morphology evolution of Co nanoparticle supported on ZrO2 surfaces

The optimization of structure-dependent activity of supported metal catalysts has driven the dynamic determination of the morphology of Co nanoparticles on ZrO2 using atomic-level simulations. Density functional theory (DFT) calculations combined with ab initio molecular dynamics (AIMD) simulations were used to investigate the surface structure, nucleation mechanism and morphology evolution of Con clusters supported on different ZrO2 facets. As the size of the Con (n = 1–5) cluster increases, the competition between Co-Co bonding and the interaction of Con clusters with the ZrO2 surface further promotes the nucleation of larger clusters. Co atoms prefer to nucleate into large clusters on both c-ZrO2(111) and t-ZrO2(101) surfaces, but this behavior is unfavorable on the m-ZrO2(-111) surface. The analysis of electric properties suggests that the types of hybrid orbitals and the number of electron transfer accounts for the difference in energies of Con clusters on ZrO2 surfaces. Further, the AIMD simulations verified the stable structure of small Co5 cluster obtained by DFT, and predicted the morphology of large Co13 clusters on ZrO2 surfaces under realistic reaction conditions, consistent with the experimental SAM images. Our work provides an intuitive understanding of structure and morphology evolution of catalysts for the targeted design of catalysts to achieve the desired activity and explore more reaction possibilities.

Effect of laser chirping on third harmonic generation in anharmonic clusters with ripple on cluster density

A proposed model delves into the resonant enhancement of third harmonic generation (THG) by a short-pulse laser inside nanoclustered plasma under the influence of density ripple. An intense chirped laser pulse incident on a clustered plasma of argon gas displaces the electrons of the medium and produces a restoring force. This force is considered to vary nonlinearly with electron displacement, leading to the anharmonic response of the electron clouds of the cluster. The nonlinear current at the third harmonic frequency arises from the perturbation of the electron density of the cluster by the ponderomotive force exerted on them by the incident laser pulse. Applying ripple in cluster density and electron density of surrounding plasma enables the phase-matching criteria for THG to be satisfied, which leads to enhanced harmonic output. An anharmonic structure of clusters exhibits strong optical nonlinearities, resulting in the plasmon resonance broadening and producing harmonics with greater efficiency. Numerical analysis shows that the chirp parameter of the laser pulse and ripple on cluster density enhance system nonlinearity causing the generation of a third harmonic of enhanced amplitude. The study explores how different factors such as laser intensity, cluster size, ripple parameter, chirp parameter, and electron excursion influence the efficiency of THG.

Revealing the nanoscale reinforcing mechanism: How topological structure of carbon black clusters influence the mechanics of rubber

The mechanical reinforcement of rubber by carbon black (CB) depends strongly on its the size and topography of CB clusters. However, the underlying mechanisms remain largely unexplored. This study uses atomic force microscopy (AFM) to probe interfacial properties at the nanoscale to elucidate the influence of the CB topological structure on macroscopic mechanical properties. A substantial amount of high-modulus bound rubber is found inside the CB aggregates, particularly in highly branched ones. This phenomenon plays a critical role in reinforcement, as corroborated by quantitative AFM nanomechanics, chain segment motion results and theoretical calculations. A quantitative analysis of the filler network reveals that the branched chain structure effectively reduces the packing spacing and improves the stress transfer efficiency.

Structure search for molecular clusters. Towards a rational understanding of their size-dependent properties

Prediction of the lowest energy structure for transition metal clusters and related systems is fundamental in cluster science. Advances in the structure search methods have reduced the computer time for structure prediction, standing on the performance of density functional theory (DFT) calculations. This perspective summarizes recent advances in the employed strategies to tackle geometrical determination of small and large metallic clusters via structure identification and rationalization of the resulting properties. Particularly, we pay attention to coinage metal clusters and noble metals due to their potential technological applications. The basics and recent achievements in structure search methods and related challenges are summarized, towards determining structural evolution accounting contributing to further development on efficient catalytic materials among other applications of technological interest.

Introduction of Niobium in the Chemistry of Octahedral Chalcogenide Clusters: Synthesis and Detailed Study of Compounds Based on Condensed and Discrete {Re5NbQ8} (Q = S or Se) Cores.

It is known that niobium practically does not form cluster chalcogenide compounds of the {M6(μ3-Q8)} type, which are widespread in the chemistry of group 6 and 7 metals. This work reports the preparation of a series of polymeric and discrete niobium-containing heterometallic clusters based on the {Re5Nb(μ3-S8)} and {Re5Nb(μ3-Se8)} cores. The compounds were prepared by the high-temperature reaction between rhenium and niobium dichalcogenides in a KCN melt. The 1D polymers K5[Re5NbQ8(CN)5] (Q = S or Se), which were formed as a result of the reaction, crystallize in the structural type of K6[Mo6Se8(CN)5], similar to the previously reported heterometallic clusters K6[Re6-xMoxQ8(CN)5] (x = 2-3). The polymers were solubilized to form discrete anionic clusters [Re5NbQ8(CN)6]4-. The structure and properties of the new clusters were investigated using a combination of X-ray diffraction analysis, UV/vis spectroscopy, high-resolution electrospray mass spectrometry, cyclic voltammetry, and DFT calculations. Among other features, the compounds showed high electrochemical activity, being able to form three redox states in solution with reversible transitions. It was found that redox potentials of the isoelectronic octahedral clusters demonstrate a strong cathodic shift in the sequence [Re5OsSe8(CN)6]3- > [Re6Se8(CN)6]4- > [Re5MoSe8(CN)6]5- > [Re5NbSe8(CN)6]6-, illustrating the effect of systematic changes in the composition of octahedral cluster cores on their properties.

Electronic structure, absorption spectra and oxidation dynamics in polyynes and dicyanopolyynes.

The advent of femtosecond to attosecond experimental tools has made now possible to study such ultrafast carrier dynamics, e.g., the spatial and temporal charge density evolution, after an initial oxidation or reduction in molecules, candidates for atomic wires like polyynes and dicyanopolyynes. Here, we study the electronic structure and hole transfer in symmetric molecules containing carbon, nitrogen and hydrogen, the first members in the series of polyynic carbynes and dicyanopolyynes, using methods based on density functional theory (DFT): constrained DFT (CDFT), time-dependent DFT (TDDFT) and real-time TDDFT (RT-TDDFT), with Löwdin population analysis, comparing many levels of theory and obtaining convergence of the results. For the same purposes, we develop a tight binding (TB) variant using all valence orbitals of all atoms. This TB variant is applied here in linear molecules, but it is also adequate for electronic structure, charge transfer and charge transport of non-linear molecules and clusters of molecules. We calculate the electronic structure, the time-dependent dipole moment and the probabilities of finding the hole at each site, their mean over time values, the mean transfer rates from the oxidation site to other sites and the frequency content (using charge as well as dipole moment oscillations). We take into account zero-point motion. The initial conditions for RT-TDDFT are obtained by CDFT. For TB, we explore different initial conditions: we place the hole at a particular orbital or distribute it among a number of orbitals; it is also possible to include phase differences between orbitals. Finally, we compare with available experimental data.

Bioinspired octanuclear copper cubane complex as an efficient molecular electrocatalyst for water oxidation

Water oxidation catalysts (WOCs) with excellent activity and stability are highly desired. Numerous efforts have been dedicated to develop WOCs mimicking the cubic structure and activity of Mn4CaO5 cluster in oxygen-evolving center (OEC) of photosynthesis system II (PSII). Herein, a octanuclear Cu cluster [Cu8(dpy{OH}O)8(OAc)4]4+ (1, dpy{OH}O− = the monoanion of the hydrated, gem-diol form of di-2-pyridyl ketone) that contains two Cu4O4 cubic fragments with bioinspired structure mimicking the Mn4CaO5 cluster of OEC of natural PSII is developed as efficient homogeneous catalyst for electrochemical water oxidation under near neutral condition for the first time. It exhibits outstanding water oxidation catalytic activity via accelerating oxygen evolution with onset overpotential of 730 mV and appreciable turnover frequency of 20.1 s−1. Collective experiments together confirmed the homogeneity and stability of cluster 1 under long-term water oxidation catalytic cycle. Kinetic study reveals the water nucleophilic attack (WNA) catalytic mechanism occurs on the coordination unsaturated Cu center of the cluster. This work provides the inspiration of the development of robust bioinspired catalyst for electrochemical water oxidation.

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ContextThe study of platinum (Pt) clusters and nanoparticles is essential due to their extensive range of potential technological applications, particularly in catalysis. The electronic properties that yield optimal catalytic performance at the nanoscale are significantly influenced by the size and structure of Pt clusters. This research aimed to identify the lowest-energy conformers for Pt18\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_{18}$$\\end{document}, Pt19\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_{19}$$\\end{document}, and Pt20\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_{20}$$\\end{document} species using Density Functional Theory (DFT). We discovered new low-symmetry conformers for Pt19\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_{19}$$\\end{document} and Pt20\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_{20}$$\\end{document}, which are 3.0 and 1.0 kcal/mol more stable, respectively, than previously reported structures. Our study highlights the importance of using density functional approximations that incorporate moderate levels of exact Hartree-Fock exchange, alongside basis sets of at least quadruple-zeta quality. The resulting structures are asymmetric with varying active sites, as evidenced by sigma hole analysis on the electrostatic potential surface. This suggests a potential correlation between electronic structure and catalytic properties, warranting further investigation.MethodsAn equivariant graph neural network interatomic potential (NequIP) within the Atomic Simulation Environment suite (ASE) was used to provide initial geometries of the aggregates under study. DFT calculations were performed with the ORCA 5 package, using functional approximations that included Generalized Gradient Approximation (PBE), meta-GGA (TPSS, M06-L), hybrid (PBE0, PBEh), meta-GGA hybrid (TPSSh), and range-separated hybrid (ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\omega $$\\end{document}B97x) functionals. Def2-TZVP and Def2-QZVP as well as members of the cc-pwCVXZ-PP family to check basis set convergence were used. QTAIM calculations were performed using the AIMAll suite. Structures were visualized with the AVOGADRO code.

Inverse Phase Transition in Droplet Clusters Levitating over the Locally Heated Water Layer.

Self-assembled microdroplet clusters can levitate above a locally heated water surface. Normally, the temperature of droplets is in the range of 50-95 °C. However, it is possible to generate clusters at lower temperatures. Here, we study the structure and behavior of such cold-stabilized droplet clusters with variable temperature. It has been established that as the temperature decreases, the role of aerodynamic forces decreases, while electrostatic forces, on the contrary, increase. We studied the behavior of droplet clusters at relatively low temperatures down to 28 °C. A chaotic motion of droplets and a phase transition were observed at the surface temperature of the water below a critical value of about Tmax = 35 ± 2 °C. The orderliness of the cluster was quantified with the Shannon/Voronoi entropy. Several stages of cluster evolution were observed and analyzed, and a mechanism of this phenomenon is discussed. An inverse phase transition in which cooling of the cluster decreases its orderliness is discussed. Frequencies of the droplets' oscillations coincide qualitatively with the frequency of the plasma oscillations within the cluster.

Ag20 Nanoclusters with Surface Azides as an Easily Functionalized Platform for Diverse Chemical Applications.

Modifying atomically precise nanocluster surfaces while maintaining the cluster core remains a key challenge. Herein, the synthesis, structure, and properties of two targeted Ag20 nanoclusters (NCs) with eight surface azide moieties, [CO3@Ag20(StBu)10(m-N3-C6H4COO)8(DMF)4] (1-m) and [CO3@Ag20(StBu)10(p-N3-C6H4COO)8(DMF)4] (1-p) are reported, where DMF is N,N-dimethylformamide. These AgNCs are designed to undergo cluster surface strain-promoted azide-alkyne cycloaddition (CS-SPAAC) reactions, introducing new functionality to the cluster surface. Reactivity is screened using model strained cyclooctynes. Reaction products and parent clusters are characterized by UV-vis, FT-IR, and NMR spectroscopies. The structure of the parent clusters and presence of surface azides is confirmed by single crystal X-ray diffraction (SCXRD) analysis. Clusters 1-m and 1-p are found to be amenable to CS-SPAAC reactions with retention of the NC frameworks, opening new routes for efficient modification of AgNC for applications.

Self-similar cluster structures in massive star-forming regions: Isolated evolution from clumps to embedded clusters

We used the dendrogram algorithm to decompose the surface density distributions of stars into hierarchical structures. These structures were tied to the multiscale structures of star clusters. A similar power-law for the mass-size relation of star clusters measured at different scales suggests a self-similar structure of star clusters. We used the minimum spanning tree method to measure the separations between clusters and gas clumps in each massive star-forming region. The separations between clusters, between clumps, and between clusters and clumps were comparable, which indicates that the evolution from clump to embedded cluster proceeds in isolation and locally, and does not affect the surrounding objects significantly. By comparing the mass functions of the ATLASGAL clumps and the identified embedded clusters, we confirm that a constant star formation efficiency of approx 0.33 can be a typical value for the ATLASGAL clumps.