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Group 12 element zinc(II)‐based d10 complexes have long been known for their inherent colorlessness, which has limited their applications in visible light‐driven photophysical and photochemical applications, despite the attractiveness of inexpensive and low‐toxicity zinc metal. Based on precedents with nickel(0) and copper(I) complexes, which also adopt the d10 electronic configuration, achieving a visible light response from zinc(II) complexes seems feasible; however, investigations and proactive design strategies specifically tailored to zinc remain lacking. In this context, the present invited concept paper highlights zinc's potential for visible light responsiveness and evaluates how molecular designs can achieve this capability. After delineating the differences between zinc and other d10 metal centers, we review recent developments in zinc complexes that exhibit visible light absorption and compare these complexes with previously reported colorless complexes to identify key distinctions. This study provides critical insights into the molecular design guidelines that are pivotal for harnessing the emerging potential of zinc for visible light responses. [ABSTRACT FROM AUTHOR]

Electrocatalysts with atomically dispersed metal sites (e.g. metal‐nitrogen‐carbon) have been deemed as promising alternatives for noble‐metal catalysts in couples of electrocatalytic reactions. However, the modulation of such atomic sites and the understanding of their interactions are still highly challenging. Herein, we propose a unique supermolecule assembly‐profile coating strategy to prepare a series of diatomic electrocatalysts by profile coating of eight Prussian blue analogues (PBAs) on supramolecular supports respectively as bimetallic sources. The detailed microstructure analysis revealed that the metal‐nitrogen‐carbon sites with four‐ (Zn−N4) and five‐coordination (Fe−N5) via the nitrogen coordination are similar to the cytochrome c oxidases. For promising electrocatalysis, such unique microstructure is able to activate oxygen molecules due to nitrogen‐bonding coordination with bimetal sites, thus leading to efficient four‐electron oxygen reduction in alkaline, neutral, and acid electrolytes. Especially, zinc group elements (e.g. Zn and Cd) with d10 electron configuration would significantly boost the nitrogen‐bonding coordination with bimetal sites to enhance electrocatalytic activity. The proof‐of‐concept for the general synthesis of advanced electrocatalysts with controllable bimetal active sites and the mechanistic understanding will promote the promising electrocatalysis by applying the similar principles. [ABSTRACT FROM AUTHOR]

First‐principles simulations can advance our understanding of phase transitions but are often too costly for the heavier elements, which require a relativistic treatment. Addressing this challenge, we recently composed an indirect approach: A precise incremental calculation of absolute Gibbs energies for the solid and liquid with a relativistic Hamiltonian that enables an accurate determination of melting and boiling points (MPs and BPs). Here, we apply this approach to the Group 12 elements Zn, Cd, Hg, and Cn, whose MPs and BPs we calculate with a mean absolute deviation of only 5 % and 1 %, respectively, while we confirm the previously predicted liquid aggregate state of Cn. At a non‐relativistic level of theory, we obtain surprisingly similar MPs and BPs of 650±30 K and 1250±20 K, suggesting that periodic trends in this group are exclusively relativistic in nature. Ultimately, we discuss these results and their implication for Groups 11 and 14. [ABSTRACT FROM AUTHOR]

The term spodium (Sp) bond is proposed to refer to a net attractive interaction between any element of Group 12 and electron‐rich atoms (Lewis bases or anions). These noncovalent interactions are markedly different from coordination bonds (antibonding Sp–ligand orbital involved). Evidence is provided for the existence of this interaction by calculations at the RI‐MP2/aug‐cc‐pVTZ level of theory, atoms‐in‐molecules, and natural bond orbital analyses and by examining solid‐state structures in the Cambridge Structure Database. [ABSTRACT FROM AUTHOR]

The formation, characterization, and dye sensitized solar cell application of nickel(II), zinc(II) and cadmium(II) ferrocenyl dithiophosphonate complexes were investigated. The multidentate monoanionic ligand [S2PFc(OH)]− (L1) was synthesized. The reaction between metal salt precursors and L1 produced Ni(II) complexes of the type [Ni{S2P(Fc)(OH)}2] (1) (molar ratio 1:2), and a tetranickel(II) complex of the type [Ni2{S2OP(Fc)}2]2 (2) (molar ratio (1:1). It also produced a Zn(II) complex [Zn{S2P(Fc)(OH)}2]2 (3), and a Cd(II) complex [Cd{S2P(Fc)(OH)}2]2 (4). Complexes 1–4 were characterized by 1H and 31P NMR, FTIR and elemental analysis, and complexes 1 and 2 were additionally analyzed by X‐ray crystallography. The first examples of dye‐sensitized solar cells (DSSCs) co‐sensitized with ferrocenyl dithiophosphonate complexes 1–4 are reported. Co‐sensitization with the ruthenium dye N719, produced the dye materials (3)‐N719 (η=8.30%) and (4)‐N719 (η=7.78%), and they were found to have a better overall conversion efficiency than the pure Ru N719 dye standard (η=7.14%) under the same experimental conditions. The DSSCs were characterized using UV/vis, cyclic voltammetry, electrochemical impedance spectroscopy (EIS), photovoltaic‐ (I−V curves), and performing incident photon‐to‐current efficiency (IPCE) measurements. [ABSTRACT FROM AUTHOR]

The reaction of 2‐cyanopyridine with N‐phenylthiosemicarbazide afforded 2‐[amino(pyridin‐2‐yl)methylidene]‐N‐phenylhydrazine‐1‐carbothioamide (Ham4ph) and crystals of 4‐phenyl‐5‐(pyridin‐2‐yl)‐2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thione (pyph3NS, 1, C13H10N4S). Crystals of methyl 2‐{[4‐phenyl‐5‐(pyridin‐2‐yl)‐4H‐1,2,4‐triazol‐3‐yl]sulfanyl}acetate (phpy2NS, 2, C16H14N4O2S), derived from 1, were obtained by the reaction of Ham4ph with chloroacetic acid, followed by the acid‐catalyzed esterification of the carboxylic acid with methyl alcohol. Crystals of bis(methanol‐κO)bis(methyl 2‐{[4‐phenyl‐5‐(pyridin‐2‐yl)‐4H‐1,2,4‐triazol‐3‐yl‐κ2N1,N5]sulfanyl}acetato)zinc(II)/cadmium(II) hexabromidocadmate(II), [Zn0.76Cd0.24(C16H14N4O2S)2(CH3OH)2][Cd2Br6] or [Zn0.76Cd0.24(phpy2NS)2(MeOH)2][Cd2Br6], 3, and dichlorido(methyl 2‐{[4‐phenyl‐5‐(pyridin‐2‐yl)‐4H‐1,2,4‐triazol‐3‐yl‐κ2N1,N5]sulfanyl}acetato)mercury(II), [HgCl2(C16H14N4O2S)] or [Hg(phpy2NS)Cl2], 4, were synthesized using ligand 2 and CdBr2 or HgCl2, respectively. The molecular and supramolecular structures of the compounds were studied by X‐ray diffractometry. The asymmetric unit of 3 is formed from CdBr3 and M(phpy2NS)(MeOH) units, where the metal centre M has a 76% occupancy of ZnII and 24% of CdII. The M2+ centre of the cation, located on a crystallographic inversion centre, is hexacoordinated and appears as a slightly distorted octahedral [MN4O2]2+ cation. The Cd centre of the anion is coordinated by two terminal bromide ligands and two bridging bromide ligands that generate [Cd2Br6]2− cadmium–bromide clusters. These clusters display crystallographic inversion symmetry forming two edge‐shared tetrahedra and serve as agents that direct the structure in the formation of supramolecular assemblies. In mononuclear complex 4, the coordination geometry around the Hg2+ ion is distorted tetrahedral and comprises two chloride ligands and two N‐atom donors from the phpy2NS ligand, viz. one pyridine N atom and the other from triazole. In the crystal packing, all four compounds exhibit weak intermolecular interactions, which facilitate the formation of three‐dimensional architectures. Along with the noncovalent interactions, the structural diversity in the complexes can be attributed to the metal centre and to the coordination geometry, as well as to its ionic or neutral character. [ABSTRACT FROM AUTHOR]

BACKGROUND In the present work, Hg ( II) is considered as one of the most dangerous elements being released excessively into the environment from various sources. Therefore, the aim of this study is the removal of Hg ( II) from wastewater effluent by synthesizing a magnetic chitosan modified with glutaraldehyde ( MCS-GA) as an adsorbent. The composite structure was characterized using SEM/ EDAX, FTIR, and XRD techniques. The adsorbent was tested by a batch system to determine the optimum conditions for removing Hg ( II) under real conditions. RESULTS The results showed that 0.5% GA effectively enhanced the removal efficiency. The maximum adsorption capacity of MCS-GA was 96 mg g−1 at pH 5.0 and 25 °C. The adsorption isotherm data obeyed the Langmuir model ( R2>0.981) and pseudo-second-order ( R2>0.996) kinetic models. It was also found that Hg ( II) adsorption on MCS-GA is inherently exothermic and occurs spontaneously. The reusability of MCS-GA was approved over 12 sequential cycles of adsorption-desorption. ANOVA analysis showed that the contact time has a synergistic effect on Hg ( II) removal, whereas pH and initial concentration have antagonistic effects. CONCLUSION Overall, the synthesized adsorbent was able to remove Hg ( II) efficiently under both experimental and real conditions. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Mercury (Hg) concentrations in aquatic environments have increased globally, exposing consumers of aquatic organisms to high Hg levels. For both aquatic and terrestrial consumers, exposure to Hg depends on their food sources as well as environmental factors influencing Hg bioavailability. The majority of the research on the transfer of methylmercury (MeHg), a toxic and bioaccumulating form of Hg, between aquatic and terrestrial food webs has focused on terrestrial piscivores. However, a gap exists in our understanding of the factors regulating MeHg bioaccumulation by non-piscivorous terrestrial predators, specifically consumers of adult aquatic insects. Because dissolved organic carbon ( DOC) binds tightly to MeHg, affecting its transport and availability in aquatic food webs, we hypothesized that DOC affects MeHg transfer from stream food webs to terrestrial predators feeding on emerging adult insects. We tested this hypothesis by collecting data over 2 years from 10 low-order streams spanning a broad DOC gradient in the Lake Sunapee watershed in New Hampshire, USA. We found that streamwater MeHg concentration increased linearly with DOC concentration. However, streams with the highest DOC concentrations had emerging stream prey and spiders with lower MeHg concentrations than streams with intermediate DOC concentrations; a pattern that is similar to fish and larval aquatic insects. Furthermore, high MeHg concentrations found in spiders show that MeHg transfer in adult aquatic insects is an overlooked but potentially significant pathway of MeHg bioaccumulation in terrestrial food webs. Our results suggest that although MeHg in water increases with DOC, MeHg concentrations in stream and terrestrial consumers did not consistently increase with increases in streamwater MeHg concentrations. In fact, there was a change from a positive to a negative relationship between aqueous exposure and bioaccumulation at streamwater MeHg concentrations associated with DOC above ~5 mg/L. Thus, our study highlights the importance of stream DOC for MeHg dynamics beyond stream boundaries, and shows that factors modulating MeHg bioavailability in aquatic systems can affect the transfer of MeHg to terrestrial predators via aquatic subsidies. [ABSTRACT FROM AUTHOR]

Luminescent metal complexes are used in photooptical devices. Zinc(II) complexes are of interest because of the ability to tune their color, their high thermal stability and their favorable carrier transport character. In particular, some zinc(II) complexes with aryl diimine and/or heterocyclic ligands have been shown to emit brightly in the blue region of the spectrum. Zinc(II) complexes bearing derivatized imidazoles have been explored for possible optoelectronic applications. The structures of two zinc(II) complexes of 5,6-dimethyl-2-(pyridin-2-yl)-1-[(pyridin-2-yl)methyl]-1 H-benzimidazole ( L), namely dichlorido(dimethylformamide-κ O){5,6-dimethyl-2-(pyridin-2-yl-κ N)-1-[(pyridin-2-yl)methyl]-1 H-benzimidazole-κ N3}zinc(II) dimethylformamide monosolvate, [ZnCl2(C20H18N4)(C3H7NO)]·C3H7NO, (I), and bis(acetato-κ2 O, O′){5,6-dimethyl-2-(pyridin-2-yl-κ N)-1-[(pyridin-2-yl)methyl]-1 H-benzimidazole-κ N3}zinc(II) ethanol monosolvate, [Zn(C2H3O2)2(C20H18N4)]·C2H5OH, (II), are reported. Complex (I) crystallized as a dimethylformamide solvate and exhibits a distorted trigonal bipyramidal coordination geometry. The coordination sphere consists of a bidentate L ligand spanning axial to equatorial sites, two chloride ligands in equatorial sites, and an O-bound dimethylformamide ligand in the remaining axial site. The other complex, (II), crystallized as an ethanol solvate. The ZnII atom has a distorted trigonal prismatic coordination geometry, with two bidentate acetate ligands occupying two edges and a bidentate L ligand occupying the third edge of the prism. Complexes (I) and (II) emit in the blue region of the spectrum. The results of density functional theory (DFT) calculations suggest that the luminescence of L results from π*←π transitions and that the luminescence of the complexes results from interligand charge-transfer transitions. The orientation of the 2-(pyridin-2-yl) substituent with respect to the benzimidazole system was found to have an impact on the calculated HOMO-LUMO gap (HOMO is highest occupied molecular orbital and LUMO is lowest unoccupied molecular orbital). [ABSTRACT FROM AUTHOR]

The influence of surfactant synergism on Zn corrosion inhibition in 0.1-M HCl aqueous solutions has been determined at room temperature. Solutions of single and mixed surfactants consisting of sodium dodecylsulfate (SDS) and N, N-dimethyldodecan-1-amine oxide (DDAO) in water and in 0.1-M HCl were also prepared at room temperature. Critical micelle concentration (CMC) data were obtained through surface tension measurements as a function of mixing composition. A regular solution model was considered to analyze CMC values. The interaction parameter ( β), the composition of mixed micelles ( x) and the activity coefficients ( f) were estimated by a regular solution model for all amphoteric-anionic mixed systems. β Vvalues showed synergism for the binary mixtures of these solutions in the absence and presence of 0.1-M HCl at all investigated compositions. Zinc corrosion in single and binary SDS/DDAO mixed solutions at 5-mM total surfactant concentrations in the presence of 0.1-M HCl was also investigated at static and dynamic conditions. The weight loss data revealed corrosion inhibition activity obeyed the following order: binary (0.75 DDAO + 0.25 SDS) > binary (0.50 DDAO + 0.50 SDS) > single DDAO > single SDS, suggesting an enhancement in the corrosion inhibition activity of DDAO in the presence of a proper amount of SDS. Conductivity time measurements show a similar trend as that obtained by a weight loss method at (0.50 DDAO + 0.50 SDS). The results were illustrated on the basis of synergistic interaction between the mixed surfactants. [ABSTRACT FROM AUTHOR]

A coupled light-harvesting antenna-charge-separation system, consisting of self-assembled zinc chlorophyll derivatives that incorporate an electron-accepting unit, is reported. The cyclic tetramers that incorporated an electron acceptor were constructed by the co-assembly of a pyridine-appended zinc chlorophyll derivative, ZnPy, and a zinc chlorophyll derivative further decorated with a fullerene unit, ZnPyC60. Comprehensive steady-state and time-resolved spectroscopic studies were conducted for the individual tetramers of ZnPy and ZnPyC60 as well as their co-tetramers. Intra-assembly singlet energy transfer was confirmed by singlet-singlet annihilation in the ZnPy tetramer. Electron transfer from the singlet chlorin unit to the fullerene unit was clearly demonstrated by the transient absorption of the fullerene radical anion in the ZnPyC60 tetramer. Finally, with the co-tetramer, a coupled light-harvesting and charge-separation system with practically 100 % quantum efficiency was demonstrated. [ABSTRACT FROM AUTHOR]

The d10 coordination polymers (CPs), [Zn(L1)(OH)]n (1) and [Cd(L2)2]n (2) were obtained from isomeric ligands 3-(6-aminpyridinium-3-yl) benzoic acid (L1) and 4-(6-aminpyridinium-3-yl) benzoic acid (L2), and characterized by elemental analyses, IR spectroscopy, single-crystal and powder X-ray diffraction. In compound 1, a spiral chain structure connected by µ2-OH- and the ZnII ions, which are further linked by the L1 ligands to give atwo-dimensional layered structure. Classical hydrogen-bonding interactions (O···H-N) between adjacent layers result in three-dimensional supramolecular structure. Compound 2 features a three-dimensional framework formed by linking [Cd2(COO)2] clusters in a bcu net. Thermal stabilities and fluorescent properties of 1 and 2 were also investigated. [ABSTRACT FROM AUTHOR]

The industrial need for high-throughput and low-cost ZnO deposition processes has triggered the development of atmospheric vapor-phase deposition techniques which can be easily applied to continuous, in-line manufacturing. While atmospheric CVD is a mature technology, new processes for the growth of transparent conductive oxides on thermally sensitive materials or flexible substrates are being developed, such as atmospheric plasma-enhanced (PE)-CVD and atmospheric spatial atomic layer deposition (ALD). In this article, the challenges and recent results on the growth of ZnO under atmospheric pressure by CVD, PE-CVD, and spatial ALD are reviewed and the use of these films as transparent electrodes in thin film solar cells are presented. [ABSTRACT FROM AUTHOR]

A reusable macroporous polybenzoxazine resin with high specific surface area was prepared as sorbent material for the removal of mercury salts. For this purpose, allyl-functionalized bis-benzoxazine was cured in dimethyl sulfoxide by thermally activated ring-opening polymerization at 180 °C for 3 d followed by a freeze-drying process. The porous structure of the resin was confirmed by SEM analysis and N2 adsorption/desorption studies at 77.3 K. Among various metal ions, namely, PbII, FeII, MnII, CuII, ZnII, and CdII, the porous polybenzoxazine resin exhibited a specific sorption behaviour towards HgII. Mainly chemisorption and to some extent adsorption mechanisms were proposed for the observed high loading capacity of the resin. As evidenced by FTIR spectral analysis, the chemisorption is attributed to the coordination system formed between free OH and tertiary amino groups in the polybenzoxazine structure and HgII ions. It was also demonstrated that the porous polybenzoxazine can be regenerated simply by treatment with acids. The resin was recycled for up to seven cycles without any significant loss of activity, as proved by sorption and desorption experiments. [ABSTRACT FROM AUTHOR]

In analogy to the previously reported tetranuclear magnesium hydride cluster with a bridged dianionic bis-β-diketiminate ligand, a related zinc hydride cluster has been prepared. The crystal structures of these magnesium and zinc hydride complexes are similar: the metal atoms are situated at the corners of a tetrahedron in which the vertices are bridged either by dianionic bis-β-diketiminate ligands or hydride ions. Both structures are retained in solution and show examples of H−⋅⋅⋅H− NMR coupling (Mg: 8.5 Hz; Zn: 16.0 Hz). The zinc hydride cluster [ NN-(ZnH)2]2 thermally decomposes at 90 °C and releases 1.8 equivalents of H2. In contrast to magnesium hydride clusters, there is no apparent relationship between cluster size and thermal decomposition temperature for the zinc hydrides. DFT calculations reproduced the structure of the zinc hydride cluster reasonably well and charge density analysis showed no bond paths between the hydride ions. This contrasts with calculations on the analogous magnesium hydride cluster in which a counter-intuitive H−⋅⋅⋅H− bond path was observed. Forcing a reduced H−⋅⋅⋅H− distance in the zinc hydride cluster, however, gave rise to a H−⋅⋅⋅H− bond path. Such weak interactions could play a role in H2 desorption. The presumed molecular product after H2 release, a Zn(I) cluster, could not be characterized experimentally but DFT calculations predicted a cluster with two localized ZnZn bonds. [ABSTRACT FROM AUTHOR]

Six new compounds with the formula [Zn(SCOR)2(N-N)] [R = -CH3 (TAc), -C6H5 (TBn); N-N = 2,2′-bipyridine (BPY), 1,10-phenanthroline (PHEN), 1,2-bis(4-pyridyl)ethylene (BPE), neocuproine (NEO)] have been obtained by the reaction of Zn(CH3COO)2 ·2H2O with the corresponding pyridine derivative and thiocarboxylate in methanol in the ratio Zn/SCOR/N-N = 1:2:1. In all compounds, the metal atom is bonded to sulfur atoms of two thiocarboxylato ligands and to two nitrogen atoms from one pyridine derivative imposing a distorted-tetrahedral geometry. The use of chelating dipyridine ligands leads to discrete monomeric entities in compounds [Zn(TAc)2(BPY)] ( 1), [Zn(TBn)2(BPY)] ( 2), [Zn(TAc)2(NEO)] ( 3), and [Zn(TBn)2(PHEN)] ( 4). On the contrary, the bridging capability of the dipyridine BPE ligand gives rise to the polymeric chains observed in compounds [Zn(TAc)2(μ-BPE)] ( 5) and [Zn(TBn)2(μ-BPE)] ( 6). The occurrence of Zn ···O weak interactions is rationalized on the basis of the νC=O shift and continuous shape measurements. Additionally, the present work demonstrates how ZnS nanoparticles can be obtained by dry thermolysis of the prepared thiocarboxylate complexes under aerobic conditions and moderate temperatures (300 °C). The analysis of the X-ray diffraction pattern and SEM/TEM images reveals the presence of ZnS crystallites below 10 nm. The influence of the N-heterocycle and thiocarboxylato ligands on the crystalline phase (blende or wurtzite), size, and purity of the resulting zinc sulfide nanoparticles is discussed. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the first series of low-coordinate bis(terphenyl) complexes of the Group 12 metals, [Zn(2,6-Naph2C6H3)2] ( 1), [Cd(OEt2)(2,6-Naph2C6H3)2] ( 2) and [Hg(OEt2)(2,6-Naph2C6H3)2] ( 3) (Naph=1-C10H7) are described. The naphthyl substituents of the terphenyl ligands confer considerable steric bulk, and as a result of limited flexibility introduce multiple conformations to these unusual systems. In the solid state, complex 1 features a two-coordinate Zn centre with the ligands oriented in a syn/ anti conformation, whereas the three-coordinate distorted T-shaped complexes 2 and 3 feature the ligands in the syn/ syn configurations. The results of DFT calculations are in good agreement with the solid-state configurations for these complexes and support the spectroscopic measurements, which indicate several conformers in solution. [ABSTRACT FROM AUTHOR]

The development of nanostructures has received notoriety due to the properties that the nanometric scale provides to the material. Among these properties, the increase in the catalytic activity due to the high specific surface area of nanostructures has been the focus of several studies. Among the nanometric catalysts that have been studied, titanate nanotubes present versatility of applications since they can be modified through the functionalization or ion exchange adding the structure metals that increase the catalytic efficiency. For the depolymerization of post‐consumer polyethylene terephthalate (PET) bottles by glycolysis, a chemical recycling method that is in accordance with the principles of sustainable development, which aims to obtain the bis(2‐hydroxyethyl) terephthalate (BHET) monomer, sodium titanate nanotubes (NaTNT) and zinc titanate nanotubes (ZnTNT) were used as catalysts. The nanostructures were efficient in the PET depolymerization reaction for 2, 3, and 4 h, converting PET into BHET with yield higher than 65% (w/w). [ABSTRACT FROM AUTHOR]

The vapor pressure of Cd in the Cd-Gd system is determined between 693 and 1045 K, and the thermodynamic activities of Cd are derived as a function of temperature for the composition range 52-86 wt.% Cd. [ABSTRACT FROM AUTHOR]

The cover image presents an artificially colored transmission electron micrograph of cadmium sulfide (CdS) nanocrystals templated on a protein microtubule (MT). This image is superimposed on a colorful brightfield image of MT‐templated CdS nanostructures bound to a silicon substrate. In the article on page 863, E. D. Spoerke and co‐workers discuss how biomediated, in vitro assembly of the MT templates to form arrays, rings, and asters facilitates the growth of complex semiconducting CdS nanostructures. [ABSTRACT FROM AUTHOR]