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The energy barrier and hysteresis temperature in two benchtop-stable D5h-symmetry HoIII single-ion magnets were significantly enhanced via the variation of the halogen anion. The coexistence of a high energy barrier of 418 K and hysteresis temperature of 15 K was observed in the bromide-ion containing HoIII single-ion magnet.

Parity-time ($\mathcal{PT}$)-symmetric systems, featuring real eigenvalues despite their non-Hermitian nature, undergo spontaneous $\mathcal{PT}$ symmetry breaking at the exceptional point (EP). The phase transition from $\mathcal{PT}$ symmetry to $\mathcal{PT}$ symmetry breaking has shown exotic functionalities in the classical realm, such as loss-induced transparency or lasing revival. This transition is also expected to produce a more unconventional effect in pure quantum $\mathcal{PT}$ devices. Here, we report experimental evidences of spontaneous $\mathcal{PT}$ symmetry breaking in a single cold $^{40}\mathrm{Ca}^{+}$ ion and, more importantly, a counterintuitive effect of perfect quantum coherence occurring at the EP. Excellent agreement between experimental results and theoretical predictions is identified. In view of the versatile role of cold ions in building a quantum memory or processor, our experiment provides an alternative platform to explore $\mathcal{PT}$-symmetric physics and utilize pure quantum EP effects.

Nitrogen Vacancy (NV) centers in diamond are a platform for several important quantum technologies, including sensing, communication and elementary quantum processors. In this letter we demonstrate the creation of NV centers by implantation using a deterministic single ion source. For this we sympathetically laser-cool single $^{15}\textrm{N}_2^+$ molecular ions in a Paul trap and extract them at an energy of 5.9\,keV. Subsequently the ions are focused with a lateral resolution of 121(35)\,nm and are implanted into a diamond substrate without any spatial filtering by apertures or masks. After high-temperature annealing, we detect the NV centers in a confocal microscope and determine a conversion efficiency of about 0.6\,$\%$. The $^{15}\textrm{NV}$ centers are characterized by optically detected magnetic resonance (ODMR) on the hyperfine transition and coherence time., 13 pages, 7 figures

Compound-specific stable chlorine isotope analysis (CSIA-Cl) is an important method for identifying sources of organochlorine contaminants and helping assess their quantification of transformation processes. However, the present CSIA-Cl is challenged by either redundant conversion pretreatment or complicated mathematical correction. To overcome the mentioned problems, a novel method has been developed for the CSIA-Cl of eight organochlorine pesticides using gas chromatography-negative chemical ionization mass spectrometry (GC-NCI-qMS) in this study. The instrument parameters, acquisition mode, and required injection amounts were optimized in terms of the precision of GC-NCI-qMS. An ionization energy of 90 eV and emission current of 90 μA were selected, and the precisions for eight organochlorine pesticides were in the range of 0.37‰–2.15‰ in single ion monitoring (SIM) mode when the injected amount was 0.50 mg L−1 (viz. 0.5 ng on column). Furthermore, when standards from Supelco and O2si were calibrated using standards from AccuStandard regarded as external isotope standard, chlorine isotope composition of α-hexachlorocyclohexane (α-HCH) and 2, 2-dichloro−1, 1-bis (4-chlorophenyl) ethylene (p, p′-DDE) in Supelco and O2si was confidently differentiated. The provenance identification method was validated by three organochlorine contaminated groundwater samples and showed a prospect in identifying the source of organochlorine pesticides.

Three mononuclear Co(II) complexes with the formulas of [Co(L1)2] (1), [Co(L2)2(CH3OH)2] (2), and [Co(L3)2(CH3OH)2] (3) (HL1 = 4-nitro-2-((E)- (propylimino)methyl)phenol, HL2 = 2,4-dinitro-6-((E)-(...

Layered double hydroxide (LDH), the only anionic clay in the environment, plays a key role in natural ion transportation. The ion retention effect of LDHs was traditionally attributed to ion exchange with low affinity. Here, we demonstrated an ultrastrong interaction between anions and LDHs induced by their inherent nanoconfinement using chromium ore processing residue (COPR) that contained several Cr(VI)-bonded LDHs as a probe. Hydrocalumite (Ca/Al-Cl LDH) was verified as the primary phase for Cr(VI) retention through two types of interactions such as ion exchange and Cr-Ca coordination. More significantly, the confined spacing between two layers of hydrocalumite provided spatial restriction and shielding effects to the intercalated Cr(VI), which enhanced Cr-Ca coordination by shortening the bonding distance and modulating the binding angle to achieve the lowest bonding energy. Such enhancement boosted Cr(VI) affinity up to 3.2 × 105 mL/g, which was 1-3 orders of magnitudes higher than ion exchange. The universality of this mechanism was verified using another Mg/Al-Cl LDH and various anions. This study broke the traditional awareness of low ion affinities of LDHs limited by single ion exchange and disclosed an essential mechanism for unexpected ion retention effects of anionic clays in nature.

The reaction of (NBu4)2Bzmal (where Bzmal2&minus, is benzylmalonate dianion) with Co(OAc)2∙4H2O gives the [Co(Bzmal)(EtOH)(H2O)]n 2D-polymer (1). The addition of 2,2&prime, bipyridine (bpy) to the starting system results in the [Co(Bzmal)(bpy)2]&middot, H2O&middot, EtOH molecular complex (2). Their molecular and crystal structures were analyzed by single-crystal X-ray crystallography. An analysis of the static magnetic data supported by the SA-CASSCF/NEVPT2 calculations revealed the presence of easy-plane magnetic anisotropy in both complexes. The AC susceptibility data confirm that both complexes show a slow field-induced (HDC = 1000 Oe) magnetic relaxation behavior.

Luminescence (nano)thermometry is an increasingly important field for remote temperature sensing with high spatial resolution. Most typically, ratiometric sensing of the luminescence emission intensities of two thermally coupled emissive states based on a Boltzmann equilibrium is used to detect the local temperature. Dependent on the temperature range and preferred spectral window, various choices for potential candidates appear possible. Despite extensive experimental research in the field, a universal theory covering the basics of luminescence thermometry is virtually nonexistent. In this manuscript, a general theoretical framework of single ion luminescent thermometers is presented that offers simple, user-friendly guidelines for both the choice of an appropriate emitter and respective embedding host material for optimum temperature sensing. The results show that the optimum performance (thermal response and sensitivity) around T0 is realized for an energy gap ∆E21 between thermally coupled levels between 2kBT0 and 3.41kBT0. Analysis of the temperature-dependent excited state kinetics shows that host lattices in which ∆E21 can be bridged by one or two phonons are preferred over hosts in which higher order phonon processes are required. Such a framework is relevant for both a fundamental understanding of luminescent thermometers but also the targeted design of novel and superior luminescent (nano)thermometers.

Recent studies have demonstrated the potential of nanoparticle-based single-ion conductors as battery electrolytes. In this work, we introduce a coarse-grained multiscale simulation approach to identify the mechanisms underlying the ion mobilities in such systems and to clarify the influence of key design parameters on conductivity. Our results suggest that for the experimentally studied electrolyte systems, the dominant pathway for cation transport is along the surface of nanoparticles, in the vicinity of nanoparticle-tethered anions. At low nanoparticle concentrations, connectivity of cationic surface transport pathways and conductivity increase with nanoparticle loading. However, cation mobilities are reduced when nanoparticles are in close vicinity, causing conductivity to decrease for suffciently high particle loadings. We discuss the impacts of cation and anion choice as well as solvent polarity within this picture and suggest means to enhance ionic conductivities in single-ion conducting electrolytes based on nanoparticle salts.

We are living in a era of alarming increases in microbial resistance to currently available antibiotics, and there is a growing need for new pharmaceutical products to treat infectious diseases. The pomegranate is an edible fruit that has virucidal and antimicrobial activities which is primarily attributable to the high concentration of hydrolysable tannins. Punicalagin, a high molecular weight tannin (1084.7), accounts for approximately 70% of the total and is concentrated in the fruit exocarp (rind). It is the focus of much research, although it is prohibitively expensive to purchase which presents an obstacle to further exploitation and development. Here we describe a method for the isolation of punicalagin from pomegranate rind extract and total pomegranate tannins using an Agilent preparative mass-directed LC–MS single quadrupole ESI-API system, where the ionization was set as negative and the mass signal acquired in Single Ion Monitoring. Thanks to the automatic fraction collector, the method can be used in automatic mode and is capable of producing punicalagin with >95% purity.

Background Oncolytic viruses are playing an increasingly important role in cancer immunotherapy applications. Given the preclinical and clinical efficacy of these virus-based therapeutics, there is a need for fast, simple, and inexpensive downstream processing methodologies to purify biologically active viral agents that meet the increasingly higher safety standards stipulated by regulatory authorities like the Food and Drug Administration and the European Agency for the Evaluation of Medicinal Products. However, the production of virus materials for clinical dosing of oncolytic virotherapies is currently limited—in quantity, quality, and timeliness—by current purification technologies. Adsorption of virus particles to solid phases provides a convenient and practical choice for large-scale fractionation and recovery of viruses from cell and media contaminants. Indeed, chromatography has been deemed the most promising technology for large-scale purification of viruses for biomedical applications. The implementation of new chromatography media has improved process performance, but low yields and long processing times required to reach the desired purity are still limiting. Results Here we report the development of an interference chromatography-based process for purifying high titer, clinical grade oncolytic Newcastle disease virus using NatriFlo® HD-Q membrane technology. This novel approach to optimizing chromatographic performance utilizes differences in molecular bonding interactions to achieve high purity in a single ion exchange step. Conclusions When used in conjunction with membrane chromatography, this high yield method based on interference chromatography has the potential to deliver efficient, scalable processes to enable viable production of oncolytic virotherapies.

For the purpose of further exploring the effect of nonperipherally attached substituents on single-ion magnet (SIMs) performance, tetrasubstituted bis[1,8,15,22-tetrakis(3-pentyloxy)phthalocyaninato]terbium double-deckers, in both the reduced form TbH[Pc(α-OC5H11)4]2 (1) and the neutral form Tb[Pc(α-OC5H11)4]2 (2), were prepared. Single-crystal X-ray diffraction analysis for 2 unambiguously demonstrates the pinwheellike molecular structure with C4 symmetry. Magnetic investigations of the two bis(phthalocyaninato)terbium double-deckers reveal their characteristic SIM nature. 2 exhibits SIM performance superior to that of 1, as revealed by the larger energy barrier of 466 K for the former species and 431 K for the latter species due to the presence of organic radical–f (radical–Tb) interactions. The enhanced SIM performance of 2 in comparison to 1 actually stems from the presence of radical–f interactions and an enhanced ligand field strength. The latter positive factor is indicated by the electrostatic pot...

The proteins MCU and EMRE form the minimal functional unit of the mitochondrial calcium uniporter complex in metazoans, a highly selective and tightly controlled Ca2+ channel of the inner mitochondrial membrane that regulates cellular metabolism. Here we present functional reconstitution of an MCU-EMRE complex from the red flour beetle, Tribolium castaneum, and a cryo-EM structure of the complex at 3.5 Å resolution. Robust Ca2+ uptake is observed into proteoliposomes containing the purified complex and is dependent on EMRE. The structure reveals a tetrameric channel with a single ion pore. EMRE is located at the periphery of the transmembrane domain and associates primarily with the first transmembrane helix of MCU. Coiled coil and juxtamembrane domains within the matrix portion of the complex adopt markedly different conformations than in a structure of a human MCU-EMRE complex, suggesting that the structures represent different conformations of these functionally similar metazoan channels.

Single-ion conducting (SIC) polymer electrolytes with a high Li transference number (tLi+) have shown the capability to enable enhanced battery performance and safety by avoiding liquid–electrolyte...

Due to low cost, environmental friendliness, good safety, superior power density and ease of operation, rechargeable aqueous ion batteries can meet the technical requirements of large-scale energy storage. Compared with aqueous single ion batteries, rechargeable aqueous hybrid ion batteries (RAHBs) have been receiving extensive interest owing to their higher operating voltage and energy density. In this review, we briefly describe the developments and challenges of rechargeable aqueous ion batteries in energy storage and systematically introduce the merits and progress of various rechargeable aqueous hybrid ion batteries. The major issues of different combinations in aqueous hybrid ion batteries along with effective solving strategies are discussed, providing a new perspective for the design and construction of high performance aqueous ion batteries. Ultimately, the challenges and prospects of RAHBs are summarized for future research.

Herein we report a stable and high-performance Dy(iii) single-ion magnet (SIM) showing an energy barrier of 944 K under zero dc field, with an open hysteresis loop up to 6 K. To the best of our knowledge, this is the highest energy barrier for a square antiprism as well as phosphine oxide based Dy-SIMs, reported so far.

Two dysprosium complexes bearing unsupported Dy–Ge/Sn metal–metal bonds are reported here, wherein the Dy–Ge and Dy–Sn bonds both contain relatively large covalency. The complexes exhibit slow relaxation of magnetization at zero field with energy barriers of 485 and 620 K, respectively, and the blocking temperature of 6 K.

The effect of subtle structural distortions on single ion magnetic anisotropy of pentagonal bipyramidal Ni(ii) complexes was probed by magnetization measurements and theoretical calculations. Reducing structural distortion on the equatorial pentagonal plane and employing strong field ligands on axial coordination sites dramatically enhance the uniaxial magnetic anisotropy in pentagonal bipyramidal Ni(ii) complexes.

A coordination compound with the composition [CoLCl2]·H2O (L = bis-condensation product of diacetyl and 2-hydrazinyl-4,6-dimethylpyrimidine) was synthesized, in which the Co(II) ion was hexacoordinated. Under applied DC fields, this compound exhibited single-ion magnet behavior. Two relaxation processes were observed when increasing the applied magnetic field from 1000 to 3200 Oe. The first relaxation (high-frequency) was observed both at 1000 Oe and 3200 Oe, while the second relaxation was only registered under a field of 3200 Oe at low frequencies (

The quantum phase transitions for one-dimensional spin-1 XXZ model with uniaxial single-ion-type anisotropy are investigated by numerical simulation. The Gaussion transition occurred between the Larged-D phase and Neel phase, which is a gapped phase. The results of ground state energy, local order parameter and entanglement entropy agree with each other. The figures for all of the physical observable are shown in the text.

Three tetracoordinated cobalt(ii) complexes with a series of unsymmetrical bidentate ligands were synthesized and crystallographically characterized. Although their static magnetic properties are similar, their dynamic magnetic properties differ drastically depending indirectly on intermolecular hydrogen-bonding interactions.

Among so-called "next generation" battery technologies, lithium metal batteries (LMBs) enabled by solid-state electrolytes are considered key to achieve rechargeable batteries with higher energy density and safety than current lithium ion batteries (LIBs). This article briefly evaluates various aspects of polymer electrolytes from history, macromolecular architecture, material classification, and electrode optimization, with special emphasis on solid polymer electrolytes (SPEs) and single ion conducting polymeric electrolytes. Representative interfaces and interphases as well as corresponding engineering strategies adopted for the anticipated goals are briefly summarized, including various approaches adopted to mitigate the shortcomings at the interfaces. Significant weight should be given for research and development of SPEs, as they could be an enabler for solid-state LMBs with attractive performance and made by comparatively easy electrode and cell processing techniques.

The reaction of a tridentate NNO donor ligand, 4-nitro-2-((2-(pyridine-2-yl)hydrazono)methyl)phenol (HL) with lanthanide(III) nitrates in the presence of triethylamine afforded a new family of neutral mononuclear LnIII complexes [Ln(NO3)(L)2(HOCH3)] (Ln = Gd; (1) Tb; (2), Dy; (3), and Ho (4). The mononuclear complexes were structurally characterized by single crystal X-ray diffraction studies which revealed a spherical tricapped trigonal prism geometry with a pseudo D3h symmetry around the LnIII centre. Static (dc) and dynamic (ac) magnetic studies have been performed on these complexes. Field-induced single-ion magnet behaviour was observed in the DyIII analogue with an effective energy barrier and an pre-exponential factor of Δ/kB = 68(2) K and τ0 = 1.8 × 10−7 s, respectively.

The prediction of solvation free energies is essential for a variety of applications. Solvation free energies of neutral systems can be predicted quite accurately. The accuracy of predictions for solvation free energies of ionic solutes dissolved in neutral solvents, however, has been reported to be worse by at least 1 order of magnitude. In this study, the performance of three approaches for solvation free energy prediction of several hundred ions dissolved in neutral solvents is evaluated. The applied methods are COSMO-RS, cluster continuum model (CCM) together with COSMO-RS, and COSMO-RS-ES. It is emphasized that the reference data for model evaluation are subject to large uncertainties stemming from the impossibility to measure the so-called elusive absolute free energies of solvation of a single ion. Consequently, such uncertainty must be considered during the evaluation of prediction methods. Therefore, a straightforward approach to account for the underlying uncertainty is applied here. Hereby, it is revealed that the true performance of the method is better than what is often reported. The average absolute deviation (AAD) of COSMO-RS is calculated to be 2.3 kcal mol-1, while applying the CCM and COSMO-RS-ES each results in AADs of 2.0 kcal mol-1. This accuracy allows for qualitative assessment of solvation free energy-dependent quantities, such as reaction rate constants.

In this study, the uniaxial and basal anisotropy governed by Cr2+ impurity ions was treated based on the Cr2+– BO 3 3 − ion vacancy model using single ion approximation. The anomalous behavior of the basal anisotropy at low temperatures was predicted.

Instead of assembling complex clusters and/or expensive lanthanide-based systems as single ion magnets, we are focusing on mononuclear cobalt(II) systems among which the complex under study, [Co( pydca)( dmpy)]2·H2O (1), shows a field supported slow magnetic relaxation on the order of seconds at low temperature ( pydca = pyridine-2,6-dicarboxylato, dmpy = 2,6-dimethanolpyridine). The low-frequency relaxation time is as slow as τ(LF) = 1.35(6) s at T = 1.9 K and BDC = 0.4 T. The properties of 1 are compared to the previously reported nickel and copper analogues which were the first examples of single ion magnets in the family of Ni(II) and Cu(II) complexes.

A recently proposed thermodynamic integration (TI) approach formulated in the framework of quantum mechanical/molecular mechanical molecular dynamics (QM/MM MD) simulations is applied to study the ...

The magnetization (both dc and ac) of pyrochlore Eu2Ti2O7 have been investigated. Ac susceptibility measurements reveal a new unusual spin freezing below 35K for pure Eu2Ti2O7. Frequency dependence of these ac peak positions indicate slow spin relaxation near this temperature and it follows the Arrhenius formula suggesting a thermally activated relaxation process. The origin of this spin freezing has been attributed essentially to a single ion process which is associated to Eu3+ spin relaxation. Non-magnetic dilution by Y3+ ions also confirms the single ion freezing., Comment: 15 pages, 6 figures

We analyze the effect of the critical behavior (line that separates the different phases in the graphic Dc vs. α, (α = J2∕J1)) on spin transport in the quantum three-dimensional anisotropic XY model at T = 0. We study the case of the cubic lattice with ion-single anisotropy, considering first neighbors interactions in-plane and out-plane which is an important lattice model of magnetism. We obtain a large variation of the peak of the AC spin conductivity in the range of large values of the critical ion-single anisotropy Dc, where the height of the single peak of the spin conductivity suffers a sudden variation in its height.

Mononuclear lanthanide-based single-ion magnets (SIMs) are known since 2003 with the discovery of SIM properties in a bis-(phthalocyaninato)lanthanide complex. A recent report on [Dy(Cpttt)2][BC6F5] indicating that it exhibits the highest known blocking temperature (60 K) has spurred fresh interest in this area. In this article, we discuss about the various requirements of lanthanide-based SIMs along with representative examples. Specifically, we describe the complexes whose coordination numbers vary from 2 to 8. We also discuss the representative examples of organometallic lanthanide complexes that can function as molecular magnets.

Two cobalt(II) metal–organic frameworks with 2-fold vertically interpenetrated (4,4) grids, namely, [Co(bpg)2(SCN)2]·3MeOH (1) and [Co(bpg)2(SCN)2]·2DMF (2) (bpg = meso-α,β-bi(4-pyridyl) glycol), w...

A β-diketonate mononuclear dysprosium compound, [Dy(TFNB)3(bpy)] (1) (TFNB = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione, bpy = 2,2′-bipyridine), has been prepared and structurally and magnetically characterized. X-ray crystallographic analysis reveals that 1 contains two crystallographically equivalent Dy(III) ions of which the eight-coordinate geometries uniformly behave as distorted square antiprismatic configurations (D4d). Magnetic investigations demonstrate that 1 displays dual relaxation processes of SMMs behavior with the effective barrier (ΔE/kB) of 23.44 K under 1200 Oe DC field, corresponding to the coexistence of two metal centers in the structure of the compound. The comparative studies of some Dy(III)-based SIMs with TFNB ligand have been conducted as well. Ab initio studies demonstrate that the Kramers doublet ground state is predominantly axial with the gz tensors of two Dy(III) fragments matching the Ising-limit factor (20) anticipated for the pure MJ = ±15/2 state.

A new chiral mononuclear Dy(III) complex, [Dy((-)-pbipy)(pdtc)3] (1) (pbipy = 4,5-pinene-2,2′-bipyridine, pdtc = pyrrolidine-dithiocarbamate) has been synthesized and structurally characterized. Magnetic studies show that complex 1 exhibits field-induced single-ion magnet behavior with τ0 = 4.2 × 10−7 s and Ueff/k = 56.7 K, which is the first example of homochiral complex derived from S-donor pyrrolidine-dithiocarboxylate with slow magnetic relaxation.

DyIII(depma)3(NO3)3 (1) and DyIII(depma)4(NO3)2(CF3SO3) (2) differ structurally by the number of depma ligands and the supramolecular interactions (π-π and C-Hπ, respectively) between anthracene moieties. They exhibit single-ion-magnetism which is coupled to photo- and mechanochromism that are partially reversible by thermal annealing. The changes are associated with the formation and destruction of excimers.

Carbide clusterfullerene DyYTiC@C80-Ih with three different metal atoms in the endohedral cluster is obtained by arc-discharge synthesis with methane as reactive gas and is successfully isolated by HPLC. The compound shows single-molecule magnetism (SMM) with magnetic hysteresis below 8 K. The SMM properties of DyYTiC@C80 are compared to those of DySc2N@C80 and the influence of the central atom in the endohedral cluster is analyzed.

The coordination geometries of the Co(II) site in the two complexes [Co(imidazole)6][BPh4]2·0.3CH3CN (1) and [Co(imidazole)6][NO3]2 (2) were observed to display the ideal symmetries Ci and D3d, respectively. Both complexes were shown to be field-induced single-ion magnets. The effective energy barrier was found to decrease as the local symmetry changed from low-symmetry Ci to high-symmetry D3d.

Using enantiopure ligands (–)/(+)-4,5-pinene-2,2′-bipyridine (LR/LS) to react with Dy(btfa)3·2H2O, respectively, a pair of Dy(III) enantiomers with the formulae Dy(btfa)3LR (R-1) and Dy(btfa)3LS (S-1, btfa− = 3-benzoly-1,1,1-trifluoroacetonate) were obtained and structurally characterized. Each Dy(III) ion in R-1 and S-1 is octa-coordinate and adopts approximately a square-antiprismatic (SAP) geometry with D4d symmetry. Studies on the magnetic and ferroelectric properties of R-1 were carried out and the investigation results of the magnetic properties revealed that it displays a slow magnetic relaxation behavior under a zero direct-current (dc) field, confirming its single-ion magnetic (SIM) characteristic with an effective energy barrier of 95.4(1.5) K. Moreover, R-1 crystallizes in the ferroelectric point group C1, and exhibits ferroelectricity with a notable remnant polarization (Pr) value of 3.75 μC cm−2 at room temperature. All these research results also suggested that R-1 and S-1 are potential multifunctional molecule-based materials combining chiroptical activities, and ferroelectric and SIM properties within one molecule.

The computational predictions of 1H NMR chemical shifts for ionic liquids were investigated. To calculate the chemical shifts more accurately, the approach of relative reference standard (RRS) was proposed. This straightforward computational technique uses organic compounds and ionic liquids that are similar to the studied ionic liquids as standards. The calculated chemical shifts of single ion pairs were strongly influenced by the anion type and the local environment. Using the RRS methodology, the calculated results agreed well with the experimental chemical shifts due to the cancellation of errors caused by the anion. Ionic clusters consisting of 4 ion pairs were also employed to model the ionic liquids with strongly coordinating anions. Large clusters slightly improve the accuracy by reducing systematic errors. Although the experimental 1H NMR data of the reference ionic liquid should be used, the RRS methodology has been shown to predict 1H NMR chemical shifts efficiently at different levels of theory.

Chiral binaphthyl substituents were incorporated onto the phthalocyanine periphery in both homoleptic and heteroleptic bis(phthalocyaninato) terbium single-ion magnets, which exhibit blocking temperatures as high as 15 K and 28 K, respectively, providing an alternative method towards enhancing the magnetic behavior.

Three new heterotrimetallic 3d-3d’-4f complexes, [Cu(L1)H2OGd(H2O)3Co(CN)6]·CH3OH·7H2O (1), [Cu4(L2)4Gd2(H2O)2Co2(CN)12]·2DMF·4CH3CN·10H2O (2) and {[Cu(L2)]2Pr(H2O)2Co(CN)6·2CH3CN·CH3OH·9H2O}n (3) were obtained and characterized. The X-ray crystallographic analyses have revealed their interesting structures: trinuclear Cu(L)GdCo (1), octanuclear ring of [{Cu(L)}2GdCo]2 (2), and one-dimensional chain of [{Cu(L)}2PrCo ]n (3). Magnetic studies indicate that the magnetic pathways of Cu-(O^O)-Gd in 1 and 2 both mediate ferromagnetic interactions, while the single ion anisotropy of PrIII dominates the magnetism of 3. These complexes provide valuable opportunity for understanding various coordination structures in this family of heterotrimetallic 3d-3d’-4f complexes.

Polycyclic aromatic hydrocarbons (PAH) were measured in sediments from 14 locations in Port Valdez, Alaska in an effort to understand changes associated with the operation of a marine terminal where crude oil delivered by pipeline was transferred to tankers for marine shipment. Samples of surficial sediment were collected annually from 1989 through 2019 at water depths of roughly 30 to 240 m by haps corer of Van Veen grab. PAH concentrations were determined by flame-ionization gas chromatography from 1989 to 2002 and by single ion monitoring gas chromatography-mass spectrometry from 2003 to 2019. Geographic coordinates and environmental variables (water depth, total organic carbon, and sediment grain-size) were also determined. The data are useful for comparisons to trend data elsewhere as well as the investigation of measurement uncertainty in chemical measurements.

In this paper we investigated the calculation of the anodic limit of two anions of ionic liquids, largely used as electrolyte of lithium batteries. Starting from a model based on calculations performed on single ions at the MP2 level of theory, we showed that the matching between calculation and experiments decreases while using more expanded basis set with respect to 6-31G**, possibly because of the destabilization of the neutral species when larger basis sets are considered. Additionally, in order to decrease the computational time, the performances for the calculation of the anodic limit obtained by means of a series of DFT functionals with increasing level of complexity (from the Generalized Gradient Approximation to the Range Separated Hybrid meta-Generalized Gradient Approximation) were compared. Overall, the best performing functionals are BMK, ωB97M-V and MN12-SX, while acceptable results can be obtained by M06-2X, M11, M08-HX and M11-L. Some less computationally expensive functionals, like CAM-B3LYP and ωB97X-D, also provide reasonable values of the anodic limit.

Improvements in the systematic uncertainty and stability of 40Ca+ optical clocks could contribute to changing the reference of time or frequency in the future.