727 results match your criteria boron clusters

Insights into the Structures and Bonding of Medium-Sized Cerium-Doped Boron Clusters.

J Phys Chem A 2021 May 7. Epub 2021 May 7.

School of Mathematics and Physics, China University of Geosciences (Wuhan), Wuhan 430074, China.

Since the discovery of metal-doped boron clusters attracted great significance to create a new class of materials, research interests have been directed to chemical bonding and structural evolution of lanthanide boride clusters. Here, we perform an extensive ground-state structure search for the CeB and CeB clusters in the size range from 9 to 18 using the Crystal structure AnaLYsis by Particle Swarm Optimization method and density functional theory optimization. It is found that the ground-state structures in both neutral and anionic series possess half-sandwich geometry. Read More

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Inhibitors of CA IX Enzyme Based on Polyhedral Boron Compounds.

Chembiochem 2021 May 3. Epub 2021 May 3.

Institute of Inorganic Chemistry, Academy of sciences of the Czech Republic, Syntheses, Area of the research institutes, 250 68, Rez near Prague, CZECH REPUBLIC.

This review describes recent progress in the design and development of inhibitors of human carbonic anhydrase IX (CA IX) based on space-filling carborane and cobalt bis(dicarbollide) clusters. CA IX enzyme is known to play crucial role in cancer cell proliferation and formation of metastases. The new class of potent and selective CA IX inhibitors combines structural motif of bulky inorganic cluster with an alkylsulfamido or alkylsulfonamido anchor group for Zn2+ ion in the enzyme active site. Read More

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Narratives of Undergraduate Research, Mentorship, and Teaching at UCLA.

Pure Appl Chem 2021 8;93(2):207-221. Epub 2021 Feb 8.

Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095, United States.

This work describes select narratives pertaining to undergraduate teaching and mentorship at UCLA Chemistry and Biochemistry by Alex Spokoyny and his junior colleagues. Specifically, we discuss how individual undergraduate researchers contributed and jump-started multiple research themes since the conception of our research laboratory. This work also describes several recent innovations in the inorganic and general chemistry courses taught by Spokoyny at UCLA with a focus of nurturing appreciation for research and creative process in sciences including the use of social media platforms. Read More

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February 2021

Formation of Fractal Dendrites by Laser-Induced Melting of Aluminum Alloys.

Nanomaterials (Basel) 2021 Apr 19;11(4). Epub 2021 Apr 19.

Department of Physics and Applied Mathematics, Stoletov Vladimir State University, Gorkii Street, 600000 Vladimir, Russia.

We report on the fabrication of fractal dendrites using laser-induced melting of aluminum alloys. We target boron carbide (B4C), which is one of the most effective radiation-absorbing materials characterized by a low coefficient of thermal expansion. Due to the high fragility of B4C crystals, we were able to introduce its nanoparticles into a stabilization aluminum matrix of AA385. Read More

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An Overview on Anodes for Magnesium Batteries: Challenges towards a Promising Storage Solution for Renewables.

Nanomaterials (Basel) 2021 Mar 22;11(3). Epub 2021 Mar 22.

Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.

Magnesium-based batteries represent one of the successfully emerging electrochemical energy storage chemistries, mainly due to the high theoretical volumetric capacity of metallic magnesium (i.e., 3833 mAh cm vs. Read More

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Recent Advances in the Synthesis of High Boron-Loaded Nucleic Acids for BNCT.

Front Chem 2021 15;9:619052. Epub 2021 Mar 15.

Laboratory of RNA Chemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia.

Boron clusters attract considerable attention as promising therapeutic tools for boron neutron capture therapy (BNCT). They combine high boron content with high chemical and biological stability, biorthogonality, and low toxicity. The development of oligonucleotide-based constructs and nucleic acid-like molecules, such as oligomeric phosphate diesters, bearing one or multiple boron clusters permits to create potential high boron-loaded agents for BNCT with good bioavailability, specifically interacting with nucleic acids inside the cell. Read More

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Boron clusters as breast cancer therapeutics.

J Inorg Biochem 2021 May 4;218:111412. Epub 2021 Mar 4.

School of Chemistry, Ryan Institute, National University of Ireland, Galway H91CF50, Ireland; CÚRAM, the SFI Research Centre for Medical Devices, National University of Ireland, Galway H91W2TY, Ireland. Electronic address:

Since the foundation of small molecule-based therapeutics over 100 years ago, their design has been dominated by organic based components. This has also been apparent in anti-cancer therapeutics in a broad range of strategies; from the older DNA chelating drugs, to the more recent molecular-targeted therapies. The main challenges facing current treatments; multidrug resistance and low therapeutic index, can potentially be alleviated by the incorporation of boron clusters. Read More

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Growth of h-BN/graphene heterostructure using proximity catalysis.

Nanotechnology 2021 Apr 16;32(27). Epub 2021 Apr 16.

Laboratory of Quantum Information, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, People's Republic of China.

In this study, a proximity catalysis route was developed for the fast growth of graphene/h-BN vertical heterostructures on Cu foils, which shows much improved synthesis efficiency (500 times faster than other routes) and good crystalline quality graphene (large single crystalline length up to 10m). The key advantage of our synthesis route is the introduction of fresh Cu foil (or Cu foam) into the high-temperature zone using a turntable. At high temperatures, Cu vapor acts as a gaseous catalyst, which can reduce the energy barrier of graphene growth and promote the decomposition of carbon sources. Read More

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Expanded Inverse-Sandwich Complexes of Lanthanum Borides: LaB and LaB.

J Phys Chem A 2021 Apr 19;125(12):2622-2630. Epub 2021 Mar 19.

Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States.

Inverse-sandwich structures have been observed recently for dilanthanide boride clusters, in which two Ln atoms sandwich a monocyclic B ring for = 7-9. An interesting question is if larger B rings are possible to form such inverse-sandwich clusters. Here we address this question by investigating LaB and LaB using photoelectron spectroscopy and quantum chemical calculations. Read More

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B: a bilayer boron cluster.

Nanoscale 2021 Feb 10;13(6):3868-3876. Epub 2021 Feb 10.

Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.

Size-selected negatively-charged boron clusters (B) have been found to be planar or quasi-planar in a wide size range. Even though cage structures emerged as the global minimum at B, the global minimum of B was in fact planar. Only in the neutral form did the B borospherene become the global minimum. Read More

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February 2021

First-Principles Identification of Single Photon Emitters Based on Carbon Clusters in Hexagonal Boron Nitride.

J Phys Chem A 2021 Feb 7;125(6):1325-1335. Epub 2021 Feb 7.

Center for the Development of Nanoscience and Nanotechnology, CEDENNA, 9170124 Santiago, Chile.

A recent study associates carbon with single photon emitters (SPEs) in hexagonal boron nitride (h-BN). This observation, together with the high mobility of carbon in h-BN, suggests the existence of SPEs based on carbon clusters. Here, by means of density functional theory calculations, we studied clusters of substitutional carbon atoms up to tetramers in h-BN. Read More

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February 2021

Worldwide Genetic Structure Elucidates the Eurasian Origin and Invasion Pathways of , Causal Agent of Dothistroma Needle Blight.

J Fungi (Basel) 2021 Feb 3;7(2). Epub 2021 Feb 3.

Department of Botany and Zoology, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic.

, the primary causal agent of Dothistroma needle blight, is one of the most significant foliar pathogens of pine worldwide. Its wide host and environmental ranges have led to its global success as a pathogen and severe economic damage to pine forests in many regions. This comprehensive global population study elucidated the historical migration pathways of the pathogen to reveal the Eurasian origin of the fungus. Read More

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February 2021

Bonding and Aromaticity in Electron-Rich Boron and Aluminum Clusters.

J Phys Chem A 2021 Feb 4;125(6):1367-1373. Epub 2021 Feb 4.

Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka44/52, 01-224 Warsaw, Poland.

In this work bonding and aromaticity of triply bonded atoms of group 13 elements (M≡M, M = B and Al) in recently characterized BAl, NaAl, and NaAl are studied. Here, I show that although molecular orbital-based analyses characterize triple bonds, the electropositive nature of group 13 elements gives these bonds unique characteristics. The bond orders derived from the delocalization index, topology of the electron density, and local characteristics of (3, -1) critical points, as defined within the context of quantum theory of atoms in molecules, do not conform with those of ordinary triple bonds. Read More

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February 2021

Structural Evolution of Boron Clusters on Ag(111) Surfaces - From Atomic Chains to Triangular Sheets with Hexagonal Holes.

Chemphyschem 2021 May 7;22(9):894-903. Epub 2021 Apr 7.

Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, Republic of Korea.

Unlike graphene and other 2D materials, borophene is 2D polymorphic with diverse hexagonal holes (HHs)-triangles ratios and the concentrations of HHs are highly substrate dependent. Here, we systematically explored the evolution of boron cluster on Ag(111) surface, B @Ag(111) (N=1∼36), to understand the nucleation of 2D boron sheet on metal surface. Our calculation showed that, with the size increasing, the structures of most stable B clusters undergo an evolution from compact triangular lattice, such as double-chains or triple-chains, to the ones with mixed triangular-hexagonal lattices. Read More

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Pressure-Induced Formation and Mechanical Properties of 2D Diamond Boron Nitride.

Adv Sci (Weinh) 2021 Jan 11;8(2):2002541. Epub 2020 Dec 11.

Tandon School of Engineering New York University Brooklyn NY 11201 USA.

Understanding phase transformations in 2D materials can unlock unprecedented developments in nanotechnology, since their unique properties can be dramatically modified by external fields that control the phase change. Here, experiments and simulations are used to investigate the mechanical properties of a 2D diamond boron nitride (BN) phase induced by applying local pressure on atomically thin h-BN on a SiO substrate, at room temperature, and without chemical functionalization. Molecular dynamics (MD) simulations show a metastable local rearrangement of the h-BN atoms into diamond crystal clusters when increasing the indentation pressure. Read More

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January 2021

Preparing (Metalla)carboranes for Nanomedicine.

ChemMedChem 2021 Jan 28. Epub 2021 Jan 28.

Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103, Leipzig, Germany.

"There's plenty of room at the bottom" (Richard Feynman, 1959): an invitation for (metalla)carboranes to enter the (new) field of nanomedicine. For two decades, the number of publications on boron cluster compounds designed for potential applications in medicine has been constantly increasing. Hundreds of compounds have been screened in vitro or in vivo for a variety of biological activities (chemotherapeutics, radiotherapeutics, antiviral, etc. Read More

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January 2021

Structures and Properties of CoB Clusters.

ACS Omega 2021 Jan 18;6(1):912-916. Epub 2020 Dec 18.

Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, Anhui, P. R. China.

A global search for the lowest energy structure of Co atom-doped boron clusters (CoB, CoB, and CoB clusters) was conducted. The lowest energy structures of them are remarkably different from those of B and CoB clusters. CoB clusters have a bowl-shaped geometry, where the Co atom is at the bottom of the bowl and is coordinated with eight B atoms. Read More

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January 2021

Diffusion Monte Carlo method on small boron clusters using single- and multi- determinant-Jastrow trial wavefunctions.

J Chem Phys 2021 Jan;154(2):024301

Institute of Atomic and Molecular Physics, Key Laboratory of High Energy Density Physics and Technology, Ministry of Education, Sichuan University, Chengdu 610065, People's Republic of China.

Multireference character in some small boron clusters could be significant, and a previous all-electron fixed-node diffusion quantum Monte Carlo (FN-DMC) calculation with the single-determinant-Jastrow (SDJ) trial wavefunction shows that the atomization energy (AE) of B is overestimated by about 1.4 eV compared with the coupled cluster method with single, doubles, and perturbative triples [CCSD(T)] results. All-electron FN-DMC calculations and those with the pseudopotential (PP) using SDJ and multi-determinant-Jastrow (MDJ) trial wavefunctions with B3LYP orbitals as well as CC calculations at different levels are carried out on B (n = 1-5, Q = -1, 0, 1) clusters. Read More

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January 2021

DMRG on Top of Plane-Wave Kohn-Sham Orbitals: A Case Study of Defected Boron Nitride.

J Chem Theory Comput 2021 Feb 13;17(2):1143-1154. Epub 2021 Jan 13.

Wigner Research Centre for Physics, P.O. Box 49, Budapest H-1525, Hungary.

In this paper, we analyze the numerical aspects of the inherent multireference density matrix renormalization group (DMRG) calculations on top of the periodic Kohn-Sham density functional theory using the complete active space approach. The potential of the framework is illustrated by studying hexagonal boron nitride nanoflakes embedding a charged single boron vacancy point defect by revealing a vertical energy spectrum with a prominent multireference character. We investigate the consistency of the DMRG energy spectrum from the perspective of sample size, basis size, and active space selection protocol. Read More

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February 2021

Exploration of Free Energy Surface and Thermal Effects on Relative Population and Infrared Spectrum of the BeB Flux-Ional Cluster.

Materials (Basel) 2020 Dec 29;14(1). Epub 2020 Dec 29.

Departamento de Fundamentos del Conocimiento, Centro Universitario del Norte, Universidad de Guadalajara, Carretera Federal No. 23, Km. 191, Colotlán 46200, Mexico.

The starting point to understanding cluster properties is the putative global minimum and all the nearby local energy minima; however, locating them is computationally expensive and difficult. The relative populations and spectroscopic properties that are a function of temperature can be approximately computed by employing statistical thermodynamics. Here, we investigate entropy-driven isomers distribution on BeB clusters and the effect of temperature on their infrared spectroscopy and relative populations. Read More

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December 2020

Terminal Mono- and Bis-Conjugates of Oligonucleotides with -Dodecaborate: Synthesis and Physico-Chemical Properties.

Int J Mol Sci 2020 Dec 26;22(1). Epub 2020 Dec 26.

Institute of Chemical Biology and Fundamental Medicine SB RAS, Lavrentiev Ave. 8, 630090 Novosibirsk, Russia.

Oligonucleotide conjugates with boron clusters have found applications in different fields of molecular biology, biotechnology, and biomedicine as potential agents for boron neutron capture therapy, siRNA components, and antisense agents. Particularly, the -dodecaborate anion represents a high-boron-containing residue with remarkable chemical stability and low toxicity, and is suitable for the engineering of different constructs for biomedicine and molecular biology. In the present work, we synthesized novel oligonucleotide conjugates of -dodecaborate attached to the 5'-, 3'-, or both terminal positions of DNA, RNA, 2'-O-Me RNA, and 2'-F-Py RNA oligomers. Read More

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December 2020

Self-assembly of a short amphiphile in water controlled by superchaotropic polyoxometalates: HSiWO vs. HPWO.

J Colloid Interface Sci 2021 Apr 7;587:347-357. Epub 2020 Dec 7.

Institut de Chimie Séparative de Marcoule, ICSM, CEA, CNRS, ENSCM, Univ Montpellier, Marcoule, France. Electronic address:

Nanometric ions, such as polyoxometalates (POMs) or ionic boron clusters, with low charge density have previously shown a strong propensity to bind to macrocycles and to adsorb to neutral surfaces: micellar, surfactant covered water-air and polymer surfaces. These association phenomena were shown to arise from a solvent-mediated effect called the (super-)chaotropic effect. We show here by combining cloud point (CP) measurements, scattering (SAXS/SANS) and spectroscopic techniques (NMR) that Keggin POMs: HSiWO (SiW) and HPWO (PW), induce the self-assembly of an organic solvent: dipropylene glycol n-propylether (CP), in water. Read More

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What are the current challenges with the application of boron clusters to drug design?

Expert Opin Drug Discov 2021 May 28;16(5):481-483. Epub 2020 Dec 28.

Institute of Medical Biology, Laboratory of Medicinal Chemistry, Polish Academy of Sciences, Lodz, Poland.

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Dynamic Nuclear Polarization Using 3D Aromatic Boron Cluster Radicals.

J Phys Chem Lett 2021 Jan 9;12(1):13-18. Epub 2020 Dec 9.

Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, United States.

A set of two dodecaborate [B(OR)] radical cluster anions containing a dense layer of fluorinated end-groups provides nuclear spin hyperpolarization via the dissolution dynamic nuclear polarization (D-DNP) technique. We show that these clusters can enhance F nuclear magnetic resonance (NMR) signals. Importantly, given the inherent radical delocalization in dodecaborate-based clusters, these species are compatible with reactive compounds such as Lewis acids, providing ∼1000-2000 times of signal enhancement for B(CF) in liquid state NMR spectroscopy experiments at 9. Read More

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January 2021

Development of Force Field Parameters for p-Carborane to Investigate the Structural Influence of Carborane Derivatives on Drug Targets by Complex Formation.

Biol Pharm Bull 2020 ;43(12):1931-1939

Faculty of Pharmacy, Meijo University.

Androgen receptor (AR) has a key role in the development and progression of prostate cancer, and AR antagonists are used for its remedy. Recently, carborane derivatives, which are carbon-containing boron clusters have attracted attention as new AR ligands. Here we determined the force field parameters of 10-vertex and 12-vertex p-carborane to facilitate in silico drug design of boron clusters. Read More

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January 2020

Carborane Guests for Cucurbit[7]uril Facilitate Strong Binding and On-Demand Removal.

J Am Chem Soc 2020 12 30;142(49):20513-20518. Epub 2020 Nov 30.

Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States.

High-affinity guests have been reported for the macrocyclic host cucurbit[7]uril (CB[7]), enabling widespread applications, but hindering CB[7] materials from being returned to their guest-free state for reuse. Here, we present polyhedral boron clusters (carboranes) as strongly binding, yet easily removable, guests for CB[7]. Aided by a Pd-catalyzed coupling of an azide anion, we prepared boron-functionalized 9-amino--carborane that binds to CB[7] with a ≈ 10 M. Read More

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December 2020

Synthesis and X-ray characterization of 15- and 16-vertex closo-carboranes.

Nat Commun 2020 11 23;11(1):5943. Epub 2020 Nov 23.

Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.

Carboranes are a class of carbon-boron molecular clusters with three-dimensional aromaticity, and inherent robustness. These endowments enable carboranes as valuable building blocks for applications ranging from functional materials to pharmaceuticals. Thus, the chemistry of carboranes has received tremendous research interest, and significant progress has been made in the past decades. Read More

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November 2020

Activation of CS and CO by Silylium Cations.

Chemistry 2021 Feb 12;27(10):3288-3291. Epub 2021 Jan 12.

Anorganische Chemie, Fakultät für Mathematik und Naturwissenschaften, Bergische Universität Wuppertal, Gaußstr. 20, 42119, Wuppertal, Germany.

The hydride-bridged silylium cation [Et Si-H-SiEt ] , stabilized by the weakly coordinating [Me NB Cl ] anion, undergoes, in the presence of excess silane, a series of unexpected consecutive reactions with the valence-isoelectronic molecules CS and CO . The final products of the reaction with CS are methane and the previously unknown [(Et Si) S] cation. To gain insight into the entire reaction cascade, numerous experiments with varying conditions were performed, intermediate products were intercepted, and their structures were determined by X-ray crystallography. Read More

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February 2021

Benchmark Data Sets of Boron Cluster Dihydrogen Bonding for the Validation of Approximate Computational Methods.

Chemphyschem 2020 12 12;21(23):2599-2604. Epub 2020 Nov 12.

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nam. 2, 16610, Prague 6, Czech Republic.

The success of approximate computational methods, such as molecular mechanics, or dispersion-corrected density functional theory, in the description of non-covalent interactions relies on accurate parameterizations. Benchmark data sets are thus required. This area is well developed for organic molecules and biomolecules but practically non-existent for boron clusters, which have been gaining in importance in modern drug as well as material design. Read More

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December 2020

The first chiral HPLC separation of dicarba-nido-undecarborate anions and their chromatographic behavior.

Talanta 2021 Jan 11;222:121652. Epub 2020 Sep 11.

Charles University, Faculty of Pharmacy Hradec Králové, Akademika Heyrovskeho 1203, Hradec Králové, 50005, Czech Republic. Electronic address:

Boron cluster compounds are extensively studied due to their possible use in medicinal chemistry, mainly in the boron neutron capture anticancer therapy and as new innovative pharmacophores. Concerning this research, the chiral separations of exceptionally stable anionic 7,8-dicarba-nido-undecaborate(1-) and metal bis(dicarbollide(1-) derivatives with asymmetric substitutions remain the unsolved challenge of the chiral chromatography nowadays. Although the successful enantioseparation of some anionic 7,8-dicarba-nido-undecaborate(1-) ion derivatives were achieved in CZE with native β-cyclodextrins, it has not been observed with HPLC, yet. Read More

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January 2021