Norm-Conserving 5f-in-Core Pseudopotentials and Gaussian Basis Sets Optimized for Tri- and Tetra-Valent Actinides (An = Pa-Lr).

Relativistic pseudopotentials (PPs) and basis sets are the workhorses for modeling heavy elements of lanthanides and actinides. The norm-conserving Goedecker-Teter-Hutter (GTH) PP is advantageous for modeling lanthanide and actinide compounds and condensed systems because of its transferability and accuracy. In this work, we develop a set of well-benchmarked GTH-type 5f-in-core PPs with scalar-relativistic effects together with associated Gaussian basis sets for the most commonly encountered trivalent and tetravalent actinides [An(III), An(IV); An = Pa-Lr].

Development of Multiscale Force Field for Actinide (An) Solutions.

A multiscale force field (FF) is developed for an aqueous solution of trivalent actinide cations An (An = U, Np, Pu, Am, Cm, Bk, and Cf) by using a 12-6-4 Lennard-Jones type potential considering ion-induced dipole interaction. Potential parameters are rigorously and automatically optimized by the meta-multilinear interpolation parametrization (meta-MIP) algorithm via matching the experimental properties, including ion-oxygen distance (IOD) and coordination number (CN) in the first solvation shell and hydration free energy (HFE). The water solvent models incorporate an especially developed polar coarse-grained (CG) water scheme named PW32 and three widely used all-atom (AA) level SPC/E, TIP3P, and TIP4P water schemes.

Improved Gaussian basis sets for norm-conserving 4f-in-core pseudopotentials of trivalent lanthanides (Ln = Ce-Lu).

The first-principles quantum chemical computations often scale as Nk (N = basis sets; k = 1-4 for linear scaling, Hartree-Fock or density functional theory methods), which makes the development of accurate pseudopotentials and efficient basis sets necessary ingredients in modeling of heavy elements such as lanthanides and actinides. Recently, we have developed 4f-in-core norm-conserving pseudopotentials and associated basis sets for the trivalent lanthanides [Lu et al., J.

Structures of Th aqueous solutions: insights from AIMD and metadynamics simulations.

Solution chemistry of actinide ions is critical to understanding the solvation behaviors and hydrolysis process. Using tetravalent thorium ion Th as a representative example, we investigate the local structures and dynamic behaviors of hydrated Th ions by molecular dynamics (AIMD) simulations using the recently developed norm-conserving pseudopotentials and basis sets optimized for actinides (J.-B.

Is pentavalent Pr(V) feasible in solid CsPrF?

The oxidation state (OS) holds significant importance in the field of chemistry and serves as a crucial parameter for tracking electrons. Lanthanide (Ln) elements predominately exhibit a +III oxidation state, with a few elements such as Ce, Pr, Nd, Tb, and Dy able to achieve a +IV oxidation state. Over the past century, numerous attempts to synthesize Pr(V) have been made without success until recent reports on Pr(V) oxides and nitride-oxide in the gas phase expanded our understanding of Ln elements.

Seasonality Affects Fluid Intake Behaviors among Young Adults in Hebei, China.

Background: Evidence on the association between environmental factors and fluid intake behavior remains limited. The current study aims to explore seasonal variations in fluid intake behaviors among young adults in China.

Methods: A prospective cohort of 79 healthy young adults (43 males and 36 females) aged 19-21 in Hebei, China, was assessed for fluid intake behaviors for four seasons.

Spectroscopic and Theoretical Identifications of Two Structural Motifs of (HO) Cluster.

Precise characterization of archetypal systems of aqueous hydrogen-bonding networks is essential for developing accurate potential functions and universal models of water. The structures of water clusters (HO) ( = 2-9) have been verified recently through size-specific infrared spectroscopy with a vacuum ultraviolet free electron laser (VUV-FEL) and quantum chemical studies. For (HO), the pentagonal prism and butterfly motifs were proposed to be important building blocks and were observed in previous experiments.

The association between hydration state and the metabolism of phospholipids and amino acids among young adults: a metabolomic analysis.

Background: Water is vital for humans' survival and general health, which is involved in various metabolic activities.

Objectives: The aim of this study was to investigate the variation in urine metabolome and associated metabolic pathways among people with different hydration states.

Methods: A metabolomic analysis was conducted using 24-h urine samples collected during a cross-sectional study on fluid intake behavior from December 9 to 11, 2021, in Hebei, China.

Analysis on fluid intake and urination behaviors among the elderly in five cities in China: a cross-sectional study.

Background: Fluid intake in the elderly may influence urination behaviors and further influence their health status. This study investigated the behaviors of fluid intake, urination and their relationships among the elderly in China.

Methods: Stratified random sampling was used to recruit the elderly participants who met the inclusion criteria from five cities in China.

Norm-Conserving 4f-in-Core Pseudopotentials and Basis Sets Optimized for Trivalent Lanthanides (Ln = Ce-Lu).

We present here a set of scalar-relativistic norm-conserving 4f-in-core pseudopotentials, together with complementary valence-shell Gaussian basis sets, for the lanthanide (Ln) series (Ce-Lu). The Goedecker, Teter, and Hutter (GTH) formalism is adopted with the generalized gradient approximation (GGA) for the exchange-correlation Perdew-Burke-Ernzerhof (PBE) functional. The 4f-in-core pseudopotentials are built through attributing 4f-subconfiguration 4f ( = 1-14) for Ln (Ln = Ce-Lu) into the atomic core region, making it possible to circumvent the difficulty of the description of the open 4f valence shell.

Theoretical prediction of a graphene-like 2D uranyl material with p-orbital antiferromagnetism.

Versatile graphene-like two-dimensional materials with s-, p- and d-block elements have aroused significant interest because of their extensive applications while there is a lack of such materials with f-block elements. Herein we report a unique one composed of the f-block element moiety of uranyl (UO ) through a global-minimum structure search. Its geometry is found to be similar to that of graphene with a honeycomb-like hexagonal unit composed of six uranyl ligands, where each uranyl is bridged by two superoxido groups and a pair of hydroxyl ligands.

On the highest oxidation states of the actinoids in AnO molecules (An = Ac - Cm): A DMRG-CASSCF study.

Actinoid tetroxide molecules AnO (An = Ac - Cm) are investigated with the ab initio density matrix renormalization group (DMRG) approach. Natural orbital shapes are used to read out the oxidation state (OS) of the f-elements, and the atomic orbital energies and radii are used to explain the trends. The highest OSs reveal a "volcano"-type variation: For An = Ac - Np, the OSs are equal to the number of available valence electrons, that is, Ac , Th , Pa , U , and Np .

Ultra-Efficient Americium/Lanthanide Separation through Oxidation State Control.

Lanthanide/actinide separation is a worldwide challenge for atomic energy and nuclear waste treatment. Separation of americium (Am), a critical actinide element in the nuclear fuel cycle, from lanthanides (Ln) is highly desirable for minimizing the long-term radiotoxicity of nuclear waste, yet it is extremely challenging given the chemical similarity between trivalent Am(III) and Ln(III). Selective oxidation of Am(III) to a higher oxidation state (OS) could facilitate this separation, but so far, it is far from satisfactory for practical application as a result of the unstable nature of Am in a high OS.

Electronic Structure and Spectroscopic Properties of Group-7 Tri-Oxo-Halides MOX (M = Mn-Bh, X = F-Ts).

The 24 trioxide halide molecules MOX of the manganese group (M = Mn-Bh; X = F-Ts), which are iso-valence-electronic with the famous MnO ion, have been quantum-chemically investigated by quasi-relativistic density-functional and ab initio correlated approaches. Geometric and electronic structures, valence and oxidation numbers, vibrational and electronic spectral properties, energetic stabilities of the monomers in the gas phase, and the decay mode of MnOF have been investigated. The light Mn-3d species are most strongly electron-correlated, indicating that the concept of a closed-shell Lewis-type single-configurational structure [Mn(d) O(p) F(p)] reaches its limits.

Norm-Conserving Pseudopotentials and Basis Sets to Explore Actinide Chemistry in Complex Environments.

We have developed a new set of norm-conserving pseudopotentials and companion Gaussian basis sets for the actinide (An) series (Ac-Lr) using the Goedecker, Teter, and Hutter (GTH) formalism with the Perdew, Burke, and Ernzerhof (PBE) exchange-correlation functional of generalized gradient approximation. To test the accuracy and reliability of the newly parameterized An-GTH pseudopotentials and basis sets, a variety of benchmarks on actinide-containing molecules were carried out and compared to all-electron and available experimental results. The new pseudopotentials include both medium- ([Xe]4f) and large-core ([Xe]4f5d) options that successfully reproduce the structures and energetics, particularly redox processes.

Coordination Sphere of Lanthanide Aqua Ions Resolved with Ab Initio Molecular Dynamics and X-ray Absorption Spectroscopy.

To resolve the fleeting structures of lanthanide Ln aqua ions in solution, we (i) performed the first ab initio molecular dynamics (AIMD) simulations of the entire series of Ln aqua ions in explicit water solvent using pseudopotentials and basis sets recently optimized for lanthanides and (ii) measured the symmetry of the hydrating waters about Ln ions (Nd, Dy, Er, Lu) for the first time with extended X-ray absorption fine structure (EXAFS). EXAFS spectra were measured experimentally and generated from AIMD trajectories to directly compare simulation, which concurrently considers the electronic structure and the atomic dynamics in solution, with experiment. We performed a comprehensive evaluation of EXAFS multiple-scattering analysis (up to 6.

Norm-Conserving Pseudopotentials and Basis Sets To Explore Lanthanide Chemistry in Complex Environments.

A complete set of pseudopotentials and accompanying basis sets for all lanthanide elements are presented based on the relativistic, norm-conserving, separable, dual-space Gaussian-type pseudopotential protocol of Goedecker, Teter, and Hutter (GTH) within the generalized gradient approximation (GGA) and the exchange-correlation functional of Perdew, Burke, and Ernzerhof (PBE). The corresponding basis sets have been molecularly optimized (MOLOPT) using a contracted form with a single set of Gaussian exponents for the s, p, and d states. The f states are uncontracted explicitly with Gaussian exponents.

The df-d Dative Bonding in a Uranium-Cobalt Heterobimetallic Complex for Efficient Nitrogen Fixation.

Single transition-metal site catalysts with s-, p-, or d-block atom anchor for nitrogen fixation have been extensively studied, and yet the studies of the f-block atom anchor are rarely reported. Thus, we investigate the feasibility of using a newly synthesized U-Co complex featuring a single Co site coordinated by tetrakis(phophinoamide) and an U anchor for N-to-NH conversion by theoretical modeling. We characterize the evolution of oxidation states of U and Co along the reaction pathways from ab initio density matrix renormalization group (DMRG) calculations, and we find that the variation of the Co → U dative bond is correlated with the changes of oxidation states.

Triple bonds between iron and heavier group-14 elements in the AFe(CO) complexes (A = Ge, Sn, and Pb).

Heteronuclear transition-metal-main-group element carbonyl anion complexes of AFe(CO)3- (A = Ge, Sn, and Pb) are prepared using a laser vaporization supersonic ion source in the gas phase, which were studied by mass-selected infrared (IR) photodissociation spectroscopy. The geometric and electronic structures of the experimentally observed species are identified by a comparison of the measured and calculated IR spectra. These anion complexes have a 2A1 doublet electronic ground state and feature an A[triple bond, length as m-dash]Fe triply bonded C3v structure with all of the carbonyl ligands bonded at the iron center.

Lanthanides with Unusually Low Oxidation States in the PrB and PrB Boride Clusters.

Lanthanide elements typically exhibit a +III oxidation state (OS) in chemical compounds with a few in +IV or even +V OS. Although lanthanides with +II OS have been observed recently in organometallic compounds, +I OS is extremely rare. Using a joint photoelectron spectroscopy and quantum theoretical study, we have found two low OS lanthanides in doped boron clusters, PrB and PrB.

Polarizable force field parameterization and theoretical simulations of ThCl -LiCl molten salts.

Recycle of thorium is an essential process in the thorium-uranium closed fuel cycle of molten salt reactor (MSR). Pyrochemical treatment of spent nuclear fuel using chloride molten salts as medium has been considered as a promising method. In this article, we performed molecular dynamics simulations on the ThCl LiCl molten salts using a polarizable force field parameterized by us from first-principles calculations.

A supramolecular radical cation: folding-enhanced electrostatic effect for promoting radical-mediated oxidation.

We report a supramolecular strategy to promote radical-mediated Fenton oxidation by the rational design of a folded host-guest complex based on cucurbit[8]uril (CB[8]). In the supramolecular complex between CB[8] and a derivative of 1,4-diketopyrrolo[3,4-]pyrrole (DPP), the carbonyl groups of CB[8] and the DPP moiety are brought together through the formation of a folded conformation. In this way, the electrostatic effect of the carbonyl groups of CB[8] is fully applied to highly improve the reactivity of the DPP radical cation, which is the key intermediate of Fenton oxidation.

Relativity-Induced Bonding Pattern Change in Coinage Metal Dimers M (M = Cu, Ag, Au, Rg).

The periodic table provides a fundamental protocol for qualitatively classifying and predicting chemical properties based on periodicity. While the periodic law of chemical elements had already been rationalized within the framework of the nonrelativistic description of chemistry with quantum mechanics, this law was later known to be affected significantly by relativity. We here report a systematic theoretical study on the chemical bonding pattern change in the coinage metal dimers (Cu, Ag, Au, Rg) due to the relativistic effect on the superheavy elements.