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Volatile organic compounds (VOCs) exhibit typically broad and mutually overlapping ro-vibrational absorption fingerprints. This complexity has so far limited the applicability of laser-based spectroscopy for VOC measurements in complex gas matrices. Here, we exploit a Vernier-type quantum-cascade laser (QCL) as an electrically tunable multiwavelength source for selective and sensitive VOC analysis. This emerging class of lasers provides access to several spectral windows by discrete Vernier tuning (“switching”) and continuous coverage within these windows (“scanning”). We present a versatile driving technique that efficiently combines the two tuning mechanisms. Applied to our Vernier QCL, it enables the rapid acquisition (within 360 ms) of high-resolution spectra from six individual spectral windows, distributed over a wide range from 1063 to 1102 cm-1. Gaining access to the broad absorption envelopes of VOCs at multiple frequencies, along with their superimposed fine structure, which are especially pronounced at a reduced sample pressure, offers completely new opportunities in VOC analysis. The potential of this approach is assessed in a direct-laser-absorption setup with acetaldehyde, ethanol, and methanol as benchmark compounds with significant spectral overlaps. A measurement precision of 1-10 ppb is obtained after integration for 10 s at amount fractions below 10 ppm, and excellent linearity is found over at least 3 orders of magnitude. Combined with our dedicated spectral fitting algorithm, we demonstrate highly selective multicompound analyses with less than 3.5% relative expanded uncertainty, even in the presence of a 40× excess of an interfering compound with complete spectral overlap., Analytical Chemistry, 95 (5), ISSN:1520-6882, ISSN:0003-2700

金沢大学学術メディア創成センター, Two-dimensional structures formed by spherical triblock patchy particles are examined by performing Monte Carlo simulations. In the model, the triblock patchy particles have two different types of patches at the polar positions. The patch sizes are different from each other, and the attractive interaction acts only between the same types of patches. The particles translate on a flat plane and rotate three-dimensionally. When varying the two patch sizes, the pressure, and interaction energy, various structures are observed. When the difference between two patch sizes is small, kagome lattices, hexagonal structures, and two-dimensional dodecagonal quasi-crystal structures are observed. When the difference between two patch sizes is large, chain-like structures are created. With lower temperature, sparse structures such as ring-like structures form., Embargo Period 12 months

The patch-clamp technique is a powerful tool that allows for a long observation of transport protein activity in real time. Experimental traces of single-channel currents can be considered as a record of the channel's conformational switching related to its activation and gating. In this work, we present a mathematically simple method of patch-clamp data analysis that assesses the connectivity and occupancy of distinct conformational substates of the channel. The proposed approach appears to be a big step forward due to its possible applications in the determination of channel substates related to disease and in the analysis of drug-channel interactions on the level of repetitive sequences of channel conformations. This is especially important in cases when molecular dynamics docking is impossible and Markovian modeling requires ambiguous optimization tasks.

The field of isomerization reactions for colloidal semiconductor magic-size clusters (MSCs) remains largely unexplored. Here, we show that MSCs isomerize via two fundamental pathways that are regulated by the acidity and amount of an incoming ligand, with CdTeSe as the model system. When MSC-399 isomerizes to MSC-422 at room temperature, the peak red-shift from 399 to 422 nm is continuous (pathway 1) and/or stepwise (pathway 2) as monitored in situ and in real time by optical absorption spectroscopy. We propose that pathway 1 is direct, with intracluster configuration changes and a relatively large energy barrier. Pathway 2 is indirect, assisted by the MSC precursor compounds (PCs), from MSC-399 to PC-399 to PC-422 to MSC-422. Pathway 1 is activated when PC-422 to MSC-422 is suppressed. Our findings unambiguously suggest that when a change occurs directly on a nanospecies, its absorption peak continuously shifts. The present study provides an in-depth understanding of the transformative behavior of MSCs via ligand-induced isomerization upon external chemical stimuli.

Compounds containing (pseudo-)tetrahedral main group (semi-)metal units are fundamentally important in three aspects. First, they provide new strategies for the stabilization of tetrahedral units, ...

This thesis describes a series of studies focused on tetranuclear model complexes of the Oxygen Evolving Complex (OEC) of Photosystem II (PSII). The OEC is a unique CaMn4O4 metallocofactor responsible for biological water oxidation, producing the dioxygen in the atmosphere required for aerobic life. Advances in spectroscopic and structural studies have deepened our understanding of the mechanism and S-state intermediates of the OEC, but details regarding the (1) role of Ca2+, (2) location of substrate waters, (3) (electronic) structures of the S-states, and (4) precise mechanism of the O−O bond formation remain debated. It is proposed that synthetic model complexes, due to tunability in aspects such as metal composition, oxidation state, geometry, and ligand environment, can provide important structure-function and structure-property relationships applicable to the OEC. However, due to synthetic challenges, series of complexes suitable for such comparisons remain rare in the literature. In Chapter 1, a brief introduction to the OEC and recent advances in the characterization of the S-state intermediates is discussed. Relationships between synthetic model complexes and how they influence mechanistic proposals for the biological system are highlighted. While it is clear spin state and cluster geometry are strongly correlated, it is important to also consider the effects of smaller, systematic changes in structure and ligand environment on the spectroscopic properties of multimetallic model complexes. Chapter 2 presents a magnetometry and spectroscopic study of a series of related CaMnIV3O4 complexes varying in the symmetry of the cluster core, ligand environment, and protonation state of the bridging oxo groups. These complexes serve as models of the CaMnIV3 cuboidal subsite, where cluster spin state has been previously proposed to be indicative of cluster geometry. Results from our study show that intact CaMnIV3O4 cubane structures can possess spin states of S = 3/2, 5/2, and 9/2, with spin state changes attributed to minor distortions within the cluster core and, importantly, from protonation state of bridging oxo moieties. Thus, interpretation of and structural assignments based on the assumption of a S = 9/2 CaMnIV3O4 subsite must be done cautiously. Chapter 3 presents a series of MnIIIMnIV3 cuboidal complexes as spectroscopic models of the S2 state of the OEC. Though not in the same geometric arrangement of Mn ions as in the OEC, these model complexes bear remarkably similar EPR spectroscopic features to the low-spin multiline signal of the S2 state. Importantly, differences within this series of essentially isostructural complexes emphasize how the electronic structures of tetranuclear Mn complexes are highly sensitive to changes in ligand environment. Specifically, the energy gap between the ground S = 1/2 spin state and higher spin excited states can be tuned based on ligand electronics, resulting in complexes where both high-spin and low-spin features can be observed by EPR spectroscopy. In Chapter 4, we expand upon our previous series of MnIIIMnIV3 model complexes utilizing a new synthetic approach to access complexes varying in Mn coordination numbers of five and six. Importantly, both proposed structures of the S2 state contain a five-coordinate MnIII poised for binding an additional aquo or hydroxide ligand in the S2 to S3 transition. Results from this study demonstrate that Mn coordination number can significantly affect the spin state and observed spectroscopy of tetramanganese-oxo clusters. The complex featuring a five coordinate MnIII possesses a ground spin state of SG = 5/2 and reactivity with water generates a MnIIIMnIV3O4 complex with all pseudo-octahedral Mn centers displaying a S = 1/2 ground state. Chapter 5 details ligand design strategies in accessing higher oxidation state clusters beyond MnIIIMnIV3. The S3-state is the last observable intermediate prior to O−O bond formation and assigned as S = 3. Previous studies from our group demonstrated the first synthetic example corroborating this spin state, concurrent with a change from antiferromagnetic coupling within the cluster core to overall ferromagnetic coupling upon oxidation to the MnIV4 oxidation state. Synthetic challenges remain in accessing related, isolable clusters. Utilizing aspects of ligand charge and basicity of a disiloxide ligand, a room temperature stable MnIV4O4 cluster was isolated and studied via magnetometry and EPR spectroscopy. Results provide a second example of a MnIV4 cluster assigned as S = 3. While unfinished, Appendix 1 presents spectroscopic studies of model MnIIIMnIV3 complexes putatively bound to biologically relevant substrates such as water, hydroxide, methanol, and ammonia. Such chemical alterations and the spectroscopic effects arising from them have been widely studied in the biological system, providing information on the electronic structure of the OEC as well as, importantly, ruling out potential substrate water binding sites. As reactivity with small molecules typically requires an open-coordination site, such studies have been rare in the literature due to the difficulty in accessing lower-coordinate Mn sites within multimetallic Mn clusters. Thus, the ongoing characterization of these reaction products are proposed to be invaluable as benchmarking tools for future mechanistic work.

Electron bifurcation is a fundamental energy coupling mechanism widespread in microorganisms that thrive under anoxic conditions. These organisms employ hydrogen to reduce CO2, but the molecular mechanisms have remained enigmatic. The key enzyme responsible for powering these thermodynamically challenging reactions is the electron-bifurcating [FeFe]-hydrogenase HydABC that reduces low-potential ferredoxins (Fd) by oxidizing hydrogen gas (H2). By combining single-particle cryo-electron microscopy (cryoEM) under catalytic turnover conditions with site-directed mutagenesis experiments, functional studies, infrared spectroscopy, and molecular simulations, we show that HydABC from the acetogenic bacteria Acetobacterium woodii and Thermoanaerobacter kivui employ a single flavin mononucleotide (FMN) cofactor to establish electron transfer pathways to the NAD(P)+ and Fd reduction sites by a mechanism that is fundamentally different from classical flavin-based electron bifurcation enzymes. By modulation of the NAD(P)+ binding affinity via reduction of a nearby iron–sulfur cluster, HydABC switches between the exergonic NAD(P)+ reduction and endergonic Fd reduction modes. Our combined findings suggest that the conformational dynamics establish a redox-driven kinetic gate that prevents the backflow of the electrons from the Fd reduction branch toward the FMN site, providing a basis for understanding general mechanistic principles of electron-bifurcating hydrogenases.

The understanding of the solvation of electrons and their degree of delocalisation in that state have been of fundamental interest ever since first discovered in alkali metal ammonia solutions. Neutral, alkali metal-doped clusters serve as ideal model systems to study solvated electrons in their size-dependent properties. The presented work focuses on the characterisation of electronic properties via angle-resolved photoelectron spectroscopy and of their magnetic properties by Stern-Gerlach deflection. The combination of both experimantal techniques reveals information on the solvated electron binding energy, electron orbital and spin angular momenta as well as the cluster rotational angular momentum. We report measurements of electron binding energies and photoelectron anisotropies in angle-dependent photoelectron spectra of lithium-doped dimethyl ether clusters as a function of cluster size distribution. Neutral singly doped lithium clusters are studied in the range from bare lithium atom to an average cluster size of 63 dimethyl ether molecules. We explain trends in electron binding energies and photoemission anisotropies on the bases of density functional calculations of LiCH3OCH3 clusters. The results of lithium-doped clusters are compared to a previous study performed in our group on NaCH3OCH3 clusters. The comparison reveals similar trends of electron binding energies and photoemission anisotropies with increasing cluster size. Yet, structural and electronic differences arise from the alkali metal substitution. In highly symmetric clusters, the highest occupied molecular orbital can delocalize over an extended region and form a symmetric charge distribution of mainly s-character, resulting in a pronounced photoemission anisotropy. The photoelectron angular distributions of Li(CH3OCH3)n reveal pronounced s-character at n=4, 5 and 6. These cluster sizes are refered to as magic clusters for the photoelectron anisotropy. Photoelectron studies of cluster size distributions are limited in their details of cluster size-resolved photoelectron contributions. Size-resolved measurements of electron binding energies and photoemission anisotropies of neutral Na(NH3)n clusters are achieved with photoelectron-photoion-coincidence-spectroscopy, for photon energies in the range of 5.5 eV - 9.9 eV. Photoelectron kinetic energy spectra in combination with ab initio calculations show three distinct ionisation pathways of the single solvated electron, each of the pathways is dominant in a certain photon energy range. One of the ionisation pathways occurs via an autoionisation process after resonant excitation of the neutral state. The excitation process is proposed to be characterised by an electron transfer of an NH3 molecule lone pair to the singly occupied molecular orbital. This excited state is characterised by a doubly occupied orbital, the so called solvated dielectron. The excited, solvated dielectron subsequently decays by electron transfer processes with the emission of low kinetic energy electrons. Besides studying the electronic states of the clusters, we exploit their magnetic character due to the unpaired electron in magnetic deflection experiments on molecular beams. The paramagnetic propeties of sodium-doped clusters with ammonia, water, methanol and dimethyl ether for cluster sizes n=1-4 are characterised by their deflection behaviour when traversing a magnetic field gradient. The spatial deflection is compared to molecular dynamics simulations based on the Zeeman interaction of a spin 1/2 system. The comparison of experiment and simulation reveals unperturbed magnetic properties of a spin 1/2 system for the smallest clusters NaNH3 and NaH2O. All larger clusters, in contrast show reduced deflection compared to simulations of a spin 1/2 system. Deviations from a spin 1/2 deflection behavior are attributed to a reduction of magnetic moment due to intracluster spin-relaxation processes. Determining effective magnetic moments for these clusters allows us to identify trends in their paramagnetic properties. The observed trends are discussed in terms of spin and rotational angular momentum interactions of the thermally accessible rovibrational density of states. We used density functional methods to determine the lowest energy cluster geometries and the rovibrational states with the harmonic oscillator and rigid rotor approximation. With this approach we find that the dominant mechanism of intracluster spin-relaxation processes in sodium-doped clusters is governed by the thermal population of spin-rotational coupled Zeeman states.

The incorporation of noncanonical amino acids (ncAAs) with different side chains into a peptide is a promising technique for changing the functional properties of that peptide. Of particular interest is the incorporation of ncAAs into peptide-derived natural products to optimize their biophysical properties for medical and industrial applications. Here, we present the first instance of ncAA incorporation into the natural product cinnamycin in streptomycetes using the orthogonal pyrrolysyl-tRNA synthetase/tRNAPyl pair from Methanosarcina barkeri. This approach allows site-specific incorporation of ncAAs via the read-through of a stop codon by the suppressor tRNAPyl, which can carry different pyrrolysine analogues. Five new deoxycinnamycin derivatives were obtained with three distinct pyrrolysine analogues incorporated into diverse positions of the antibiotic. The combination of partial hydrolysis and MS/MS fragmentation analysis was used to verify the exact position of the incorporation events. The introdu...

A set of metal carbonyl cluster-boronic acid conjugates of the group VIII metals (Fe, Ru, and Os) were synthesized and their antiproliferative effects measured against two breast cancer cell lines (MCF-7 and MDA-MB-231) and a noncancerous breast epithelial (MCF-10A) cell line. The cytotoxicity followed the order Ru > Os > Fe for the MDA-MB-231 cells, although the latter two exhibited similar cytotoxicity against MCF-7 and MCF-10A cells. The osmium species {Os3(CO)10(μ-H)[μ-SC6H4-p-B(OH)2]} (2) could be chemically oxidized to its hydroxy analogue [Os3(CO)10(μ-H)(μ-SC6H4-p-OH)] (2-OH), which showed comparable cytotoxicity. Mode of action studies pointed to an apoptotic pathway for cell death. Ministry of Education (MOE) Nanyang Technological University Published version This work was supported by Nanyang Technological University and the Ministry of Education (Research grant no. RG121/18).

Despite the numerous titanium-oxo clusters (TOCs) which have been reported, the nature of small clusters (nuclearity < 10) as model compounds showed large deviation from that of nanoscale TiO materials. Therefore, theoretical and experimental studies for large TOCs merit more attention. We recently prepared and crystallographically characterized a series of large TOCs: Ti11O15(OiPr)16(Cophen) (1), Ti11O15(OiPr)16(Mnphen) (2), Ti10O14(OEt)16(Mnphen)2 (3), and Ti10O14(OEt)16(Mnphphen)2 (4) (phen = 1,10-phenanthroline, phphen = 4,7-biphenyl-phen). These compounds are derivatives of a Ti12 parent cluster by replacing one or two of the five-coordinated titanium atoms of the Ti12 cluster with a transition metal M, Co(II) and Mn(II), that is chelated by a phen group. The effects of mono- and bis-substituted Mphen on the charge and structure of the clusters are discussed. Theoretical evaluation of the frontier orbitals of the clusters is carried out on the basis of the precisely defined crystal structures. Different from the dye molecule to TiO core charge transfer for the dye-modified TOCs, charge transfer in these clusters is from TiO/TiOM to phen/Mphen. The effects of different metal ions and the number of substituted Mphen moieties on the photocurrent properties are evaluated. The results will be of interest to research on cluster chemistry, especially on the TOC chemistry.

International audience; Structures and bonding of various homo- and heterometallic metallaborane clusters are described, which are stabilized in the coordination sphere of early transition metals. For example, the bimetallic triborane species [{Cp*Mo(CO)}2{μ–η3:η3-B3H7}], 2, has been synthesized from the pyrolysis of an in situ generated intermediate, produced from the reaction of [Cp*Mo(CO)3Me], 1, and [LiBH4·THF] with an excess amount of [BH3·THF]. Superficially cluster 2 is isostructural but not isoelectronic with [(Cp*MoCl)2B3H7] (I). Both clusters 2 and I contain a bimetallic template bridged by {B3H7} moiety. Cluster 2 is denoted as a unique saturated and unsubstituted closo bimetallic B3H7 cluster. Theoretical output implies that saturation in such clusters brings thermodynamic stability. Further, we have developed a new strategy for the synthesis of various heterometallic metal-rich metallaborane clusters. For example, pyrolysis of an intermediate, obtained from the reaction of [Cp*MoCl4], 4, and [LiBH4·THF] with cobalt and iron carbonyl compounds yielded triply bridging hydrido(hydroborylene), [{Cp*Mo(CO)2}2Co(CO)3BH(μ-H)], 5, tetrametallic μ4-boride, [{Cp*Mo(CO)2}2(μ4-B)(μ-H){Co2(CO)5}], 6, triple decker complex, [(Cp*Mo)2{μ–η6:η6-B4H4Co2(CO)5}(μ-H)2], 7, metal-rich dimolybdaborane cluster, [(Cp*Mo)2Co2 (CO)3(μ-CO)3B3H3(μ-H)2], 8, and mixed-metal cluster, [(Cp*Mo)2B4H8Fe(CO)3], 9. All the molecules have been characterized by 1H, 11B{1H}, and 13C{1H} NMR spectroscopy, mass spectrometry, infrared (IR) spectroscopy, and single-crystal X-ray diffraction studies for clusters 2 and 5–9. The electron counting rules and density functional theory (DFT) calculations provided further insight into the bonding and electronic structures of these clusters.

Copper cluster chemistry with a multifunctional 2,4,6-trimercaptotriazine thio-ligand in the presence of triphenylphosphine as a co-ligand is investigated. In a typical case, a reaction of copper(I) chloride with 2,4,6-trimercaptotriazine (tmtH3) in a mixture of acetonitrile–methanol at room temperature, followed by the addition of solid Ph3P (1:1:2 molar ratio) yielded a yellow compound of composition, [Cu3Cl2(tmtH2)(PPh3)6] 1. However, this reaction when performed in dimethyl formamide (DMF) in the presence of Et3N Lewis base (Cu:tmtH3:PPh3::1:1:2 molar ratio) yielded yellow crystals of hexa-nuclear cluster, [Cu6(tmt)2(PPh3)6].(DMF)2 2. A single crystal x-ray crystallography revealed that in tri-nuclear cluster 1, all three sulfur donor atoms are bonded to three CuI ions, resulting in the two four coordinated Cu(S,Cl,P2) and one Cu(N,S,P2) cores. As regards hexa-nuclear cluster 2, each Cu is bonded to one N, one S and one P donor atom, generating six Cu(N,S,P) coordination cores, and each Cu has a distorted trigonal planar geometry. Two parallel triazine rings are held in a close proximity of 3.063 A by six Cu–S bridges. Spectroscopic, luminescence and versatility of bonding modes are described. The tri-nuclear cluster, with a new coordination mode of (tmtH2)−, represents a rare example in copper-heterocyclic-2-thione chemistry. Copper(I) chloride with tmtH3 in acetonitrile–methanol mixture has afforded a novel trinuclear luminescent cluster. Reaction of copper(I) chloride with 2,4,6-trimercaptotriazine and PPh3 in CH3CN–CH3OH mixture yielded a trinuclear luminescent cluster of composition, [Cu3Cl2(tmtH2)(PPh3)6].

The continuously decreasing size of device features in microelectronics draws growing attention to the structuring of silicon at the molecular level with powerful tools provided by synthetic chemistry. Silicon clusters are of particular importance in this regard not only as potential precursors for silicon deposition but also as well-defined model systems for bulk and surfaces of silicon at the nanoscale as well as possible starting points for future construction of molecularly precise device structures. This review aims to give a comprehensive overview about the state of the art in the synthesis of molecular silicon clusters, which are grouped into (1) electron-precise saturated clusters, (2) soluble polyhedral Zintl anions, and (3) unsaturated silicon clusters, the so-called siliconoids. Particular attention is paid to functionalization as it is generally considered a necessary prerequisite for the design and construction of more extended systems. The interrelations between the three different classes of molecular silicon clusters, e.g., arising from the introduction of negatively charged functional groups, are highlighted on grounds of NMR properties and computed electronic structures.

The chemistry of discrete molecular chains constituted by metals in low oxidation states, displaying metal-metal proximity and stabilized by suitable metal-bridging, assembling ligands comprising at least one soft donor atom is comprehensively reviewed; complexes with a single (hard or soft) bridging atom (e.g., μ-halide, μ-sulfide, or μ-PR2etc.) as well as "closed" metal arrays (that fall in the realm of cluster chemistry) are excluded. The focus is on transition metal-based systems, with few excursions to cases combining transition and post-transition elements. Most relevant supporting ligands have neutral C, P, O, or S donor (mainly, N-heterocyclic carbene, phosphine, ether, thioether) or anionic donor (mainly phenyl, ylide, silyl, phosphide, thiolate) groups. A supporting-ligand-based classification of the metal chains is introduced, using as the classifying parameter the number of "bites" (i.e., ligand bridges) subtending each intermetallic separation. The ligands are further grouped according to the number of donor atoms interacting with the metal chain (called denticity in the following) and the column of the Periodic Table to which the set of donor atoms belongs (in ascending order). A complementary metal-based compilation of the complexes discussed is also provided in a concise tabular form.

© 2021 The Authors. Allosteric drugs have been attracting increasing interest over the past few years. In this context, it is common practice to use high-throughput screening for the discovery of non-natural allosteric drugs. While the discovery stage is supported by a growing amount of biological information and increasing computing power, major challenges still remain in selecting allosteric ligands and predicting their effect on the target protein’s function. Indeed, allosteric compounds can act both as inhibitors and activators of biological responses. Computational approaches to the problem have focused on variations on the theme of molecular docking coupled to molecular dynamics with the aim of recovering information on the (long-range) modulation typical of allosteric proteins. AIRC IG 2017 - ID. 20019 project; AIRC Fellowship; EC Research Innovation Action H2020 Programme Project HPC-EUROPA3 (INFRAIA-2016-1-730897)

The effects of atmospheric aerosols on our climate are one of the biggest uncertainties in global climate models. Calculating the pathway for the formation of pre-nucleation clusters that become ae...

International audience; Bright NIR phosphorescence from octahedral molybdenum clusters has been known since the 1980s. However, their behavior toward NIR excitation has never been investigated. Here we report their abilities to emit NIR light and produce singlet oxygen upon two-photon absorption. This behavior is observed in solution, in the solid state, and when clusters are embedded homogeneously in a poly(dimethylsiloxane) matrix. Such discoveries open new perspectives in several fields like optoelectronics, photodynamic therapy, or bioimaging.

For decades, chemists have explored cluster compounds according to theoretical models that have proved too simplistic to accurately predict cluster properties, stabilities and functions. By incorporating molecular symmetry into existing cluster models, we can better study real polyatomic molecules and have new guidelines for their design. This symmetry-adapted cluster model allows us to discover substances that shatter the conventional notion of clusters. Theoretical predictors will point to the viability of new clusters, whose syntheses can be realized with parallel advances in experimental methods. This Perspective describes these modern experimental and theoretical strategies for cluster design and how they may give rise to new fields in cluster chemistry. Theoretical models of clusters that account for molecular symmetry offer guidelines for their design. This Perspective describes the models and how we can synthesize the clusters thus designed.

A triple-decker complex of tungsten, [(Cp*W)2{μ-η6:η6-B4H4Co2(CO)5}(H)2] (1; Cp* = η5-C5Me5), with a planar middle deck has been isolated by thermolysis of an in situ formed intermediate from the reaction of Cp*WCl4 and LiBH4 with Co2(CO)8. In addition, we have also isolated another triple-decker complex, [(Cp*W)2{μ-η6:η6-B5H5Fe(CO)3}(H)2] (4), having a puckered central ring, from a similar reaction with Fe2(CO)9. Clusters 1 and 4 are unprecedented examples of a triple-decker complex having a 24-valence electron with bridging hydrogen atoms.

The stereocontrol of chiral metal clusters and nanoclusters has become a focus of interest in metal cluster chemistry due to their promising applications in asymmetric catalysis. Despite being a ge...