Anchoring Atomically Precise Chiral Bismuth Oxido Nanoclusters on Gold: The Role of Amino Acid Linkers.

The adsorption of chiral molecules onto metallic surfaces triggers electron spin polarization at the interface, paving the way for applications in chiral opto-spintronics. However, the spin effects sensitively depend on the binding and ordering of the chiral species on surfaces. This study explores the adsorption of chiral thioether-functionalized atomically precise bismuth oxido nanoclusters (BiO-NCs) on gold (Au) surfaces, extending the conventional approach of using thiol-containing molecules and complexes to nanoclusters.

Deposition of Nanosized Amino Acid Functionalized Bismuth Oxido Clusters on Gold Surfaces.

Bismuth compounds are of growing interest with regard to potential applications in catalysis, medicine, and electronics, for which their environmentally benign nature is one of the key factors. One thing that currently hampers the further development of bismuth oxido-based materials, however, is the often low solubility of the precursors, which makes targeted immobilisation on substrates challenging. We present an approach towards the solubilisation of bismuth oxido clusters by introducing an amino carboxylate as a functional group.

Coatings of magnetic composites of iron oxide and carbon nitride for photocatalytic water purification.

Magnetic composites of iron oxide (α-FeO and FeO) and carbon nitride materials (CN) were synthesized a microwave assisted hydrothermal method starting from iron salts and CN, which was obtained by thermal decomposition of dicyandiamide. The as-prepared composites with iron oxide loadings of 0.5 ω%-6 ω% were characterized by powder X-ray diffraction (PXRD), diffuse reflectance UV-vis spectroscopy, magnetization measurements, nitrogen adsorption measurements and thermogravimetric analyzes (TGA).

Polymorphism and Visible-Light-Driven Photocatalysis of Doped BiO:M (M = S, Se, and Re).

δ-BiO:M (M = S, Se, and Re) with an oxygen-defective -type structure is obtained by a coprecipitation method starting from the bismuth oxido cluster [BiO(OMc)(dmso)]·2dmso·7HO () in the presence of additives such as NaSO, NaSeO, NHReO, NaSeO·5HO, and NaSO. The coprecipitation of the starting materials with aqueous NaOH results in the formation of alkaline reaction mixtures, and the cubic bismuth(III)-based oxides BiO(SO) (), BiO(SeO) (), BiO(ReO) (), BiO(SeO) (), and BiO(SO)(SO) () are obtained after microwave-assisted heating; formation of compound is the result of partial oxidation of sulfur. The compounds , , , and absorb UV light only, whereas compound absorbs in the visible-light region of the solar spectrum.

Are Heavy Pnictogen-π Interactions Really "π Interactions"?

The noncovalent interactions of heavy pnictogens with π-arenes play a fundamental role in fields like crystal engineering or catalysis. The strength of such bonds is based on an interplay between dispersion and donor/acceptor interactions, and is generally attributed to the presence of π-arenes. Computational studies of the interaction between the heavy pnictogens As, Sb and Bi and cyclohexane, in comparison with previous studies on the interaction between heavy pnictogens and benzene, show that this concept probably has to be revised.

Structural Changes during the Growth of Atomically Precise Metal Oxido Nanoclusters from Combined Pair Distribution Function and Small-Angle X-ray Scattering Analysis.

The combination of in situ pair distribution function (PDF) analysis and small-angle X-ray scattering (SAXS) enables analysis of the formation mechanism of metal oxido nanoclusters and cluster-solvent interactions as they take place. Herein, we demonstrate the method for the formation of clusters with a [Bi O ] core. Upon dissolution of crystalline [Bi O (OH) (NO ) ]⋅3 H O in DMSO, an intermediate rapidly forms, which slowly grows to stable [Bi O ] clusters.

Porous carbon-carbon composite electrodes for vanadium redox flow batteries synthesized by twin polymerization.

Highly porous carbon-carbon composite electrodes have been synthesized by surface twin polymerization on a macroporous polyacrylonitrile (PAN)-based substrate. For this purpose the compound 2,2'-spirobi[benzo-4-1,3,2-dioxasiline] (Spiro), being a molecular precursor for phenolic resin and silica, was polymerized onto PAN-based felts with subsequent thermal transformation of the hybrid material-coated felt into silica-containing carbon. The following etching step led to high surface carbon-carbon composite materials, where each carbon component served a different function in the battery electrode: the carbon fiber substrate possesses a high electron conductivity, while the amorphous carbon coating provides the catalytic function.

Evaluation of bismuth-based dispersion energy donors - synthesis, structure and theoretical study of 2-biphenylbismuth(iii) derivatives.

A series of 2-biphenyl bismuth(iii) compounds of the type (2-PhCH)BiX [n = 0 (1); n = 1, X = Cl (2), Br (3), I (4), Me (5); n = 2, X = Cl (6), Br (7), I (8)] has been synthesized and analyzed with focus on intramolecular London dispersion interactions. The library of the compounds was set up in order to investigate the Biπ arene interaction by systematic variation of X. The structural analysis in the solid state revealed that the triarylbismuth(iii) compound 1 shows an encapsulation of the metal atom but the distances between the bismuth atom and the phenyl centroids amount to values close to or larger than 4.

Thin Coatings of α- and β-BiO by Ultrasonic Spray Coating of a Molecular Bismuth Oxido Cluster and their Application for Photocatalytic Water Purification Under Visible Light.

Thin coatings of BiO were deposited on glass substrates by ultrasonic spray coating of THF solutions of the molecular precursor [BiO(OMc)(DMSO)] ⋅ 2DMSO ⋅ 7HO (OMc=OCCH) followed by hydrolysis and subsequent annealing. Depending on the synthetic protocol, the bismuth oxido cluster was transformed into either α- or β-BiO. The as-synthesized BiO coatings were characterized by powder X-ray diffraction (PXRD), thickness measurements, diffuse reflectance UV-Vis spectroscopy (DRS), photoluminescence (PL) spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM).

Thin Coatings of α- and β-BiO by Ultrasonic Spray Coating of a Molecular Bismuth Oxido Cluster and their Application for Photocatalytic Water Purification Under Visible Light.

https://doi.org/10.1002/open.

From a Cerium-Doped Polynuclear Bismuth Oxido Cluster to β-BiO:Ce.

The simultaneous hydrolysis of Bi(NO)·5HO and Ce(NO)·6HO results in the formation of novel heterometallic bismuth oxido clusters with the general formula [BiO(NO)(DMSO)]:Ce (DMSO = dimethyl sulfoxide; cerium content <1.50%), which is demonstrated by single-crystal X-ray diffraction analysis. The incorporation of cerium into the cluster core is a result of the interplay of hydrolysis and condensation of the metal nitrates in the presence of oxygen.

Balancing Donor-Acceptor and Dispersion Effects in Heavy Main Group Element π Interactions: Effect of Substituents on the Pnictogen⋅⋅⋅π Arene Interaction.

High-level ab initio calculations using the DLPNO-CCSD(T) method in conjunction with the local energy decomposition (LED) were performed to investigate the nature of the intermolecular interaction in bismuth trichloride adducts with π arene systems. Special emphasis was put on the effect of substituents in the aromatic ring. For this purpose, benzene derivatives with one or three substituents (R=NO , CF , OCHO, OH, and NH ) were chosen and their influence on donor-acceptor interaction as well as on the overall interaction strength was examined.

Synthesis of Mg and Zn diolates and their use in metal oxide deposition.

The synthesis of complexes [M(OCHMeCHNMeCH)] (5, M = Mg; 7, M = Zn) is described. Treatment of MeHNCHCHNMeH (1) with 2-methyloxirane (2) gave diol (HOCHMeCHNMeCH) (3), which upon reaction with equimolar amounts of MR (4, M = Mg, R = Bu; 6, M = Zn, R = Et) gave 5 and 7. The thermal behavior and vapor pressure of 5 and 7 were investigated to show whether they are suited as CVD (= chemical vapor deposition) and/or spin-coating precursors for MgO or ZnO layer formation.

Spirocyclic tin salicyl alcoholates - a combined experimental and theoretical study on their structures, Sn NMR chemical shifts and reactivity in thermally induced twin polymerization.

The spirocyclic tin salicyl alcoholate, 4H,4'H-2,2'-spirobi[benzo[d][1,3,2]dioxastannine] (1), and its 6,6'-dimethoxy (2) and 8,8'-di-tert-butyl-6,6'-dimethyl derivative (3) were synthesized and thermally induced twin polymerization of precursor 2 was performed to give a SnO2-containing hybrid material. Studies on the molecular structures of 1-3 were carried out using 119Sn{1H} CP MAS NMR spectroscopy and DFT calculations. Crystallization of compound 3 from dimethyl sulfoxide solution provided the Lewis acid-base adduct 3(dmso)2 exhibiting a hexacoordinated tin atom in the solid state, in agreement with the results of the spectroscopic and DFT calculation data.

Evaluation of dispersion type metal···π arene interaction in arylbismuth compounds - an experimental and theoretical study.

The dispersion type Bi···π arene interaction is one of the important structural features in the assembly process of arylbismuth compounds. Several triarylbismuth compounds and polymorphs are discussed and compared based on the analysis of single crystal X-ray diffraction data and computational studies. First, the crystal structures of polymorphs of PhBi () are described emphasizing on the description of London dispersion type bismuth···π arene interactions and other van der Waals interactions in the solid state and the effect of it on polymorphism.

Homo- and Heteroleptic Coordination Polymers and Oxido Clusters of Bismuth(III) Vinylsulfonates.

The synthesis and characterization of six homo- and heteroleptic coordination polymers and oxido clusters of bismuth(III) vinylsulfonates are reported. The solvent-mediated reaction of BiPh and vinylsulfonic acid in ethanol produces [{Ph Bi(O SCH=CH )} ] (1), which crystallizes as a one-dimensional coordination polymer as a result of bridging sulfonato ligands accompanied by intermolecular Bi⋅⋅⋅ π(arene) London dispersion interactions. In solution, compound 1 equilibrates to give [{PhBi(O SCH=CH ) } ] (2) and BiPh .

γ-BiO - To Be or Not To Be? Comparison of the Sillenite γ-BiO and Isomorphous Sillenite-Type BiSiO.

The "controlled" synthesis of metastable γ-BiO by solution based approaches was reported several times recently, but the formation of BiSiO in the presence of trace amounts of silicates renders the results to be questionable. Here, the preparation of the Sillenite γ-BiO and the Sillenite-type BiSiO starting from the polynuclear bismuth oxido cluster [BiO(OCCH)(DMSO)] is reported. γ-BiO crystallizes after calcination at 800 °C of the silicate-free hydrolysis product "[BiO(OH)]" on a silver sheet.

β-Ketoiminato-based copper(ii) complexes as CVD precursors for copper and copper oxide layer formation.

The synthesis of ketoiminato copper(ii) complexes [Cu(OCRCHC(CH3)NCH2CH2X)(μ-OAc)]2 (X = NMe2: 4a, R = Me; 4b, R = Ph. X = OMe: 5, R = Me) and [Cu(OCRCHCMeNCH2CH2NEt2)(OAc)] (6, R = Me) from RC(O)CHC(CH3)N(H)CH2CH2X (X = NMe2: 1a, R = Me; 1b, R = Ph. X = NEt2: 1c, R = Me.

Magnesium β-ketoiminates as CVD precursors for MgO formation.

The synthesis and characterization of bis(ketoiminato)magnesium(ii) complexes of composition [Mg(OCRCHCHRNCHCHX)] (X = NMe: 3a, R = R = Me; 3b, R = Me, R = Ph. X = OMe: 3c, R = R = Me) are reported. Complexes 3a-c are accessible by the reaction of C(O)RCHCHRN(H)CHCHX (X = NMe: 1a, R = R = Me; 1b, R = Me, R = Ph.

High-Level Ab Initio Calculations of Intermolecular Interactions: Heavy Main-Group Element π-Interactions.

This work reports high-level ab initio calculations and a detailed analysis on the nature of intermolecular interactions of heavy main-group element compounds and π systems. For this purpose we have chosen a set of benchmark molecules of the form MR , in which M=As, Sb, or Bi, and R=CH , OCH , or Cl. Several methods for the description of weak intermolecular interactions are benchmarked including DFT-D, DFT-SAPT, MP2, and high-level coupled cluster methods in the DLPNO-CCSD(T) approximation.

2D and 3D Coordination Networks of Polynuclear Bismuth Oxido/Hydroxido Sulfonato Clusters from Low Temperature Solid-State Metathesis Reactions.

Solid-state metathesis (SSM) reactions between Bi(NO ) ⋅5 H O and potassium benzene-1,2-disulfonate (=1,2-BDSK ), sodium benzene-1,3-disulfonate (=1,3-BDSNa ) allows access to the first 2D, {[Bi O (OH) (1-2BDS) (NO ) ⋅4 H O]⋅11 H O} and {[Bi O (OH) (1,3-BDS) ⋅12 DMSO]⋅3 DMSO⋅4 H O} , and 3D, {[Bi O (OH) (1,3-BDS) ⋅4 H O]⋅6 H O} , polymeric networks of sulfonato encapsulated polynuclear bismuth oxido/hydroxido clusters.

Electronic Structure Calculations and Experimental Studies on the Thermal Initiation of the Twin Polymerization Process.

Presented here is a combined computational and experimental study on the thermal initiation process of the twin polymerization. Although thermally initiated twin polymerization offers a versatile scheme for obtaining hybrid organic/inorganic nanocomposite materials, the mechanism for its initiation is very different from the proton-initiated twin polymerization. In this study, the basic mechanism of the early steps of the polymerization process of 4 H,4 H'-2,2'-spirobi[benzo[d][1,3,2]dioxasiline] was investigated by using electronic structure calculations in conjunction with experimental differential scanning calorimetry studies.

Ester formation at the liquid-solid interface.

A chemical reaction (esterification) within a molecular monolayer at the liquid-solid interface without any catalyst was studied using ambient scanning tunneling microscopy. The monolayer consisted of a regular array of two species, an organic acid (trimesic acid) and an alcohol (undecan-1-ol or decan-1-ol), coadsorbed out of a solution of the acid within the alcohol at the interface of highly oriented pyrolytic graphite (HOPG) (0001) substrate. The monoester was observed promptly after reaching a threshold either related to the increased packing density of the adsorbate layer (which can be controlled by the concentration of the trimesic acid within the alcoholic solution via sonication or extended stirring) or by reaching a threshold with regards to the deposition temperature.

Impact of regional socioeconomic variation on coordination and cost of ambulatory care: investigation of claims data from Bavaria, Germany.

Objectives: A considerable proportion of regional variation in healthcare use and health expenditures is to date still unexplained. The aim was to investigate regional differences in the gatekeeping role of general practitioners and to identify relevant explanatory variables at patient and district level in Bavaria, Germany.

Design: Retrospective routine data analysis using claims data held by the Bavarian Association of Statutory Health Insurance Physicians.