A Spectroscopic and Computational Evaluation of Uranyl Oxo Engagement with Transition Metal Cations.

We report the synthesis and characterization of five novel Cd/UO heterometallic complexes that feature Cd-oxo distances ranging from 78 to 171% of the sum of the van der Waals radii for these atoms. This work marks an extension of our previously reported Pb/UO and Ag/UO complexes, yet with much more pronounced structural and spectroscopic effects resulting from Cd-oxo interactions. We observe a major shift in the U═O symmetric stretch and significant uranyl bond length asymmetry.

Systematic Study of Solid-State U(VI) Photoreactivity: Long-Lived Radicalization and Electron Transfer in Uranyl Tetrachloride.

Reported are the syntheses, structural characterizations, and luminescence properties of three novel [UOCl] bearing compounds containing substituted 1,1'-dialkyl-4,4'-bipyridinum dications (i.e., viologens).

Structural, Spectroscopic, and Computational Analysis of Halogen- and Hydrogen-Bonding Effects within a Series of Uranyl Fluorides with 4-Halopyridinium.

Reported are the syntheses and characterization of five compounds containing one-dimensional uranyl fluoride chains charge balanced by 4-X-pyridinium (X = H, F, Cl, Br, I) cations. Structural analysis reveals molecular assembly via noncovalent interactions in the second coordination sphere with the X···O interaction distances ranging from 2.987(7) to 3.

Orbital Engineering Mediated by Cation Conjugation in Luminescent Uranyl-Organic Hybrid Materials.

A series of compounds of the form [HAr] [UO X ] is reported here, wherein Ar is systematically varied between pyridine (1-X), quinoline (2-X), acridine (3-X), 2,5-dimethylpyrazine (4-X), quinoxaline (5-X), and phenazine (6-X), and X=Cl or Br. With greater conjugation in the organic cation, a larger quenching in uranyl luminescence is observed in the solid state. Supporting our luminescence experiments with computation, we map out the potential energy diagrams for the singlet and triplet states of both the [HAr] cations and [UO Cl ] anion in the crystalline state, and of the assembly.

Utility of all-pyrazole heteroscorpionates in f-element chemistry.

Since their discovery in 1966, scorpionate ligands have been utilized to make coordination compounds for a variety of applications such as: studying organometallic reactions, biomimetic complexes, light-emitting materials and single-ion magnets. The recent development of a solvent-free pyrazole substitution chemistry has yielded the quantitative synthesis of asymmetrically functionalized all-pyrazole heteroscorpionate ligands. In this frontier article, we highlight the utility of all-pyrazole heteroscorpionates, specifically, nitro-trispyrazolylborates, in f-element chemistry.

Tuning the optical and magnetic properties of lanthanide single-ion magnets using nitro-functionalized trispyrazolylborate ligands.

We report the synthesis, crystal structures, photophysical and magnetic properties of 11 novel lanthanide complexes with the asymmetrically functionalized trispyrazolylborate ligand 4-nitrotrispyrazolylborate, 4-NOTp: [Ln(4-NOTp)] (Ln = La-Dy, except Pm). In-depth photophysical characterization of the ligands luminescence, reflectance and absorption spectroscopic techniques, decay lifetimes, quantum yields supported by time-dependent density functional theory (TD-DFT) and natural bond order (NBO) analysis reveal that -NOTp ligands are dominated by intra-ligand charge transfer (ILCT) transitions and that second-sphere interactions are critical to the stabilization of the T state of -NOTp ligands and hence their ability to sensitize Ln emission. The luminescence properties of the complexes indicate that 4-NOTp is a poor sensitizer of Ln emission, unlike 3-NOTp.

Bandgap modification in 0D tellurium iodide perovskite derivatives incorporation of polyiodide species.

Halide perovskites provide a versatile platform for exploring the effect of non-covalent interactions, including halogen bonding, on material properties such as band gap, luminescence, and frontier orbital landscape. Herein we report six new zero-dimensional tellurium iodide perovskite derivatives, consisting of [TeI] octahedra charge balanced by one of several X-Py cations (X = H, Cl, Br, I, and Py = pyridinium). These compounds also feature robust halogen bonding between [TeI] octahedra and polyiodides in the form of I (1-4), I (5), or adjacent octahedra (4 and 6).

Plutonium Hybrid Materials: A Platform to Explore Assembly and Metal-Ligand Bonding.

We report the synthesis of five new hybrid materials containing the [PuCl] anion and charge-balancing, noncovalent interaction donating 4-X-pyridinium (X = H, Cl, Br, I) cations. Single crystals of the title compounds were grown and harvested from acidic, chloride-rich, aqueous media, and their structures were determined via X-ray diffraction. Compounds -, (4XPyH)[PuCl], and , (4IPyH)[PuCl]·2Cl, exhibit two distinct sheet-like structure types.

Suspended sediment releases in rivers: Toward establishing a safe sediment dose for construction projects.

The harmful effects of suspended sediment (SS) exposures on aquatic ecosystems have been well documented. Integrating this knowledge into the management plans of in-stream construction projects that cause SS releases remains challenging. Commonly, these projects have fixed scopes that require decisions about trade-offs between elevated SS concentrations (SSC, mg∙L) and duration of exposure (DoE, h).

A novel symmetric pyrazine (pyz)-bridged uranyl dimer [UOCl(HO)(Pyz)]: synthesis, structure and computational analysis.

Herein we report on the synthesis of (HPyz)[UOCl(HO)(Pyz)]·2HO which features a novel pyrazine-bridged uranyl dimer, [UOCl(HO)(Pyz)]. A rigorous computational and experimental analysis of this compound was performed to fully explore the influence of coordination on the electronic structure and potential charge-transfer characteristics of this dimer, revealing a delocalized π-system across the bridging pyrazine and the axial components of both uranyl centers. Electrostatic surface potentials, used to rationalize the observed assembly, indicate a decreased basicity of the uranyl oxo [UOCl], and signify a lessened capacity for the terminal -yl oxos of the [UOCl(HO)(Pyz)] dimer to participate in supramolecular assembly.

A spectroscopic, structural, and computational study of Ag-oxo interactions in Ag/UO complexes.

Twelve novel Ag/UO heterometallic complexes have been prepared and characterized structural, spectroscopic, and computational methods to probe the effects of Ag-oxo interactions on bonding and photophysical properties of the uranyl cation. Structural characterization reveals Ag-oxo interaction distances ranging from 2.475(3) Å to 4.

Insight on noncovalent interactions and orbital constructs in low-dimensional antimony halide perovskites.

Reported is a series of eight antimony halide perovskite derivatives synthesized from acidic aqueous solutions of antimony oxide and halogen substituted pyridines. These materials feature anionic one-dimensional antimony halide (SbX; X = Cl, Br, I) chains or ribbons charge-balanced by organic -halopyridinium cations (XPy; X = H, Cl, Br) which assemble into three-dimensional networks halogen and hydrogen noncovalent interactions (NCIs) between ion pairs. Computational density functional theory (DFT) based natural bonding orbital (NBO) and density of state (DOS) methods were utilized to map the band structure and quantify and categorize noncovalent interaction strength and type.

Pb-Oxo Interactions in Uranyl Hybrid Materials: A Combined Experimental and Computational Analysis of Bonding and Spectroscopic Properties.

Reported are the syntheses and characterization of six new heterometallic UO/Pb compounds. These materials feature rare instances of M-oxo interactions, which influence the bonding properties of the uranyl cation. The spectroscopic effects of these interactions were measured using luminescence and Raman spectroscopy.

A categorical assessment of dose-response dynamics for managing suspended sediment effects on salmonids.

Many studies have investigated the consequences of exposure to fine-grained suspended sediments (SS) on aquatic organisms. Exposure has two components-concentration and duration-and can be expressed as dose, where we define suspended sediment dose (SSD: mg·h·L) as the product of suspended sediment concentration (SSC: mg·L) and duration of exposure (DoE: h). We evaluated these three measurement endpoints for managing SS effects on salmonids by assembling and analyzing all published SS dose-response observations.

Structural Diversity of Lanthanide 3-Nitrotrispyrazolylborates: Tunable Nuclearity and Intra-Ligand Charge Transfer Sensitization of Visible and NIR Ln Emission.

Reported are the syntheses, crystal structures, and photophysical properties of 28, novel lanthanide compounds across five structural types, [Ln(3-NOTp)(NO)] (-Ln, Ln = La-Tm, except Pm), [BuN][Ln(3-NOTp)(NO)] (-Ln, Ln = Yb, Lu), [Eu(3-NOTp)Cl(HO)]·2PrOH (-Eu), [{Ln(3-NOTp)}(μ-CO)]·MeOH (-Ln, Ln = La-Gd, except Pm), and [{Ln(3-NOTp)}(μ-OMe)(μ-O)] (-Ln, Ln = Pr-Tb, except Pm) with the 3-nitrotrispyrazolylborate (3-NOTp) ligand. The reaction of methanol or isopropanol solutions of LnX (X = Cl, NO) with the tetrabutyl ammonium salt of the flexidentate 3-NOTp ([BuN][3-NOTp]) yields Ln(3-NOTp) complexes of various nuclearities as either monomers (-Ln, -Ln, -Eu), dimers (-Ln), or tetramers (-Ln) owing to the efficient conversion of atmospheric CO to CO (dimers) or ligand controlled solvolysis of lanthanide ions (tetramers). 3-NOTp is an efficient sensitizer for both the visible and near-IR (NIR) emissions of most of the lanthanide series, except thulium.

Bimetallic uranyl/cobalt(II) isothiocyanates: structure, property and spectroscopic analysis of homo- and heterometallic phases.

We report the synthesis and characterization of a family of UO22+/Co2+ isothiocyanate materials containing [UO2(NCS)5]3- and/or [Co(NCS)4]2- building units charged balanced by tetramethylammonium cations and assembled via SS or SOyl non-covalent interactions (NCIs), namely (C4H12N)3[UO2(NCS)5], (C4H12N)2[Co(NCS)4], and (C4H12N)5[Co(NCS)4][UO2(NCS)5]. The homometallic uranyl phase preferentially assembles via SS interactions, whereas in the heterometallic phase SOyl interactions are predominant. The variation in assembly mode is explored using electrostatic surfaces potentials, revealing that the pendant -NCS ligands of the [Co(NCS)4]2- anion is capable of outcompeting those of the [UO2(NCS)5]3- anion.

Craving mediates the association between attentional bias to alcohol and in vivo alcoholic beverage consumption in young social drinkers.

Objective: Franken's attentional bias hypothesis proposes that attentional bias to alcohol (ABA) activates craving, which motivates alcohol consumption behavior. While this hypothesis was put forward to account for alcohol dependence, the present study tested whether Franken's model may potentially contribute to explaining variation in beer consumption among young social drinkers.

Method: ABA was measured by presenting participants with dual videos, one showing alcoholic beverages and the other non-alcoholic beverages, and assessing relative attention to each using a visual probe procedure.

An Americium-Containing Metal-Organic Framework: A Platform for Studying Transplutonium Elements.

The synthesis, structure, and spectroscopic characterization of the first transplutonium metal-organic framework (MOF) is described. The preparation and structure of Am-GWMOF-6, [Am (C H O ) (H O) ][(C H N )], is analogous to that of the isostructural trivalent lanthanide-only containing material GWMOF-6. The presented MOF architecture is used as a platform to probe Am coordination chemistry and guest-enhanced luminescent emission, whereas the framework itself provides a means to monitor the effects of self-irradiation upon crystallinity over time.

Novel Heterometallic Uranyl-Transition Metal Materials: Structure, Topology, and Solid State Photoluminescence Properties.

Six new uranyl hybrid materials have been synthesized solvothermally utilizing the ligands 2,2'-bipyridine-3,3'-dicarboxylic acid (HL) and 2,2':6',2''-terpyridine (TPY). The six compounds are classified as either molecular complexes (IO connectivity), [(UO)(L)(TPY)]·HO (1), [Ni(TPY)][(UO)(L)]·3HO (2), and [Cu(TPY)][(UO)(L)]·3HO (3), or 3D metal-organic frameworks (MOFs, IO connectivity), [Cu(UO)(OH)(CHO)(L)(TPY)]·6HO (4), [Zn(UO)(OH)(NO)(CHO)(L)(TPY)]·4HO (5), and Na[Ni(UO)(OH)(O)(L)]·9HO (6). A discussion of the influence of transition metal incorporation, chelating effects of the ligand, and synthesis conditions on the formation of uranyl materials is presented.

A Thorium Metal-Organic Framework with Outstanding Thermal and Chemical Stability.

A new thorium metal-organic framework (MOF), Th(OBA) , where OBA is 4,4'-oxybis(benzoic) acid, has been synthesized hydrothermally in the presence of a range of nitrogen-donor coordination modulators. This Th-MOF, described herein as GWMOF-13, has been characterized by single-crystal and powder X-ray diffraction, as well as through a range of techniques including gas sorption, thermogravimetric analysis (TGA), solid-state UV/Vis and luminescence spectroscopy. Single-crystal X-ray diffraction analysis of GWMOF-13 reveals an interesting, high symmetry (cubic Ia d) structure, which yields a novel srs-a topology.

Life-history variation along environmental and harvest clines of a northern freshwater fish: Plasticity and adaptation.

Plasticity, local adaptation and evolutionary trade-offs drive clinal variation in traits associated with lifetime growth. Disentangling the processes and determinants that cause these traits to vary helps to understand species' responses to changing environments. This is particularly urgent for exploited populations, where size-selective harvest can induce life-history evolution.

Plutonium chlorido nitrato complexes: ligand competition and computational metrics for assembly and bonding.

Four new [Pu(iv)Cln(NO3)6-n]2- (n = 0, 2, 3) and [Pu(vi)O2Cl3(NO3)]2- containing materials were crystallized from acidic, aqueous media and structurally characterized. The anions are assembled via hydrogen and halogen bonding motifs, which are rationalized computationally. The Pu-NO3 and -Cl bonds were probed using QTAIM and NLMO analyses and found to be polar and largely ionic.

Restricted Speciation and Supramolecular Assembly in the 5f Block.

Hybrid materials bearing elements from the 5f block display a rich diversity of coordination geometries, connectivities, and assembly motifs. Exemplary in this regard have been uranyl coordination polymers, which feature a wide range of secondary building units resulting from hydrolysis and oligomerization of the [UO ] cation. An alternative approach to novel materials, however, suppresses hydrolysis and relies on non-covalent interactions (e.

Thermochromic Uranyl Isothiocyanates: Influencing Charge Transfer Bands with Supramolecular Structure.

The synthesis and structural characterization of seven new [UO(NCS)]- and [UO(NCS)Cl]-containing materials charge balanced by 4-phenylpyridinium or 4,4'-bipyridinium cations are reported. Assembly of these materials occurs via a diverse set of noncovalent interactions, with the most prevalent involving the terminal sulfur atoms, which can both accept hydrogen bonds and/or form S···S and S···O interactions. The electrostatic potential of the [UO(NCS)] and [UO(NCS)Cl] anions was calculated and mapped on the 0.