Salt Molecules Research Articles

Electrochemical grafting of diazonium salts on silica-terminated versus H-terminated silicon

Diazonium salts are one of the most widely used molecules for functionalising electrode surfaces, due to their high reactivity toward a range of different electrodes but have mostly been studied on carbon and gold. Recent work has demonstrated that diazonium salts can be reduced on silica-terminated silicon (Si/SiOx) despite silica (SiOx) being an electrically insulating material, but this interesting phenomenon was only demonstrated on one specific crystal orientation, Si(111) using specific diazonium salts molecules – a more complete understanding of the electrochemical properties of these silica-terminated silicon electrodes remains unclear. In this work, we develop a thorough understanding of the reduction of diazonium compounds on silica-terminated silicon using silicon with different crystal orientation and using nano-structured silicon surfaces that are chemically etched to simultaneously expose different crystal orientations. A comparison between the reduction process on oxide free silicon (Si–H) and silica-terminated Si is then made to reveal the effect of the crystal orientation (amorphous vs crystalline) and the insulating nature of the distal surface (Si‒H vs SiOx) on the reduction process. Results show that diazonium salts form, well-packed thin films on silica-terminated silicon regardless of the crystal orientation of the silicon. The rate of diazonium reduction was found to be sensitive to the crystal orientation of Si only when the diazonium salts are in direct contact with the crystal plane (i.e. in contact with Si–H) as opposed to when there is a thin layer of native amorphous oxide material in between. The reduction rate is sufficiently slow on silica-terminated silicon that at slow scan rates, the system reaches a steady state current and become diffusion controlled. This is not observed on oxide-free silicon electrodes which are observed to be governed by a kinetically driven mechanism. These findings deepen our understanding of the electrochemical activity of silica-terminated silicon surfaces which are widely used in solar cells, electronics, chemical and biosensors.

Exploring the anti-diabetic activity of 2,6-diamino-4-chloropyrimidinium-hydrogen oxalate conjugates: Synthesis, crystal structure, quantum computational, drug-likeness, molecular docking and dynamics simulation

Inhibiting carbohydrate-hydrolyzing enzyme has been considered as an effective approach for controlling starch digestion and postprandial blood glucose level. The aim of this study, the salt molecule was prepared to identify potentially effective compound against diabetic activity and discover the inhibitory mechanism of the targeted enzyme, which is determined by In-silico techniques. And also perform the quantum chemical calculation to provide insights about the internal motions of the molecule at the atomic level. The 2,6-diamino-4-chloropyrimidinium-hydrogen oxalate (C4H6ClN4+. C2HO4-) was newly synthesized molecule, which is detailly discussed in this present work. The title compound has been confirmed by single-crystal X-ray diffraction studies, and this structure was refined by the least-square refinement method. The crystal compound exhibited the P-1 space group (centrosymmetric) and the following unit cell parameters: a = 5.5778(6)Å, b = 9.6687(10)Å, c = 9.9144(10)Å, α = 116.342(1) °, β = 92.610(1) °, γ = 106.370(1) °, Z = 2. The molecular structure is stabilized by the networks of N–H···O, O–H···O, C–H···O, and N–H···N hydrogen bond interactions. The Hirshfeld surface (HS) analysis and fingerprint plots revealed strong intermolecular interaction between the molecules. The structural optimization, frontier molecular orbital (FMO), molecular reactivity, molecular electrostatic potential (MEP), and mulliken atomic charges were generated by the density functional theory (DFT) calculated at B3LYP/6-311G++ (d,p) theory level. Drug-likeness and physicochemical properties were predicted. The molecular docking analysis was showed a binding energy of −8.96 kcal/mol within the active site of alpha-amylase, which is responsible for anti-diabetic activity. The protein-ligand complex stability was verified using molecular dynamics studies with 100 ns.

Co-pyrolysis of algae and lignocellulosic biomass in molten salts to produce N-doped carbon for supercapacitor application

Conventional pyrolysis strategies present challenges in maintaining the nitrogen fraction and improving the electrical conductivity of the product carbon at the same time. Co-pyrolysis of algae and lignocellulosic biomass with different temperature-controlled procedures in molten Na2CO3–K2CO3 is innovatively proposed to produce N-doped capacitive carbon. Results show that interactions between algae and bamboo in the presence of molten salt incorporate more nitrogen species into the carbon matrix and increase carbon yield. Co-pyrolysis with an optimal switching temperature of two-stage pyrolysis improves the nitrogen amount in carbon and the carbon yield by up to 108.7 % and 34.7 %, respectively. Through diffusion and infiltration, the liquid molten carbonates increase the contact area between the salt molecules and the carbon matrix, resulting in superior and uniform capacitive carbon. The resulting carbon shows a high specific capacitance of 306.2 F/g at 0.25 A/g with a cycling stability of 91.3 % after 5000 cycles, due to its hierarchical porous structure, high specific surface area (1326.58 m2/g) and abundant pyridine-N/pyrrolidine-N (81 %). Therefore, applying co-pyrolysis in molten carbonates with two-stage pyrolysis to produce high-yield N-doped carbon for supercapacitor application is proved to be promising.

Laboratory exploration of a novel method to protect silicate relics against salt efflorescence by directional induction of water

Salt efflorescence is one of the critical problems for the preservation of immovable silicate relics. Salt efflorescence mainly comes from continuous cycles of crystallization/dissolution or hydration/dehydration of salts in confined pores in silicate relics. Many protocols have been developed in attempts to alleviate possible salt damages with minor success because of endless water and salt feed from underground. In this study, we propose and design a novel technique for salt damage prevention and protection of immovable relics. Materials with higher water-absorbing ability than matrix are applied to control the water and salt migration direction in simulated sand samples. The distribution of moisture content on the surface of sand is followed by hyperspectral imaging. It appears that water and salt molecules will preferentially transport towards positions containing higher water-absorbing material. Both organic and inorganic high water-absorbing materials show effective in controlling the water and salt migration direction, which provides a new approach for the prevention and protection of salt efflorescence in silicate cultural relics.

Probing iodide/iodonium salt interactions with single-walled carbon nanotubes for resilient electrochemical capacitor

Self-standing films from single-walled carbon nanotubes (SWCNTs) were successfully used as electrochemical capacitors’ (ECs) electrode material, which exhibited state-of-the-art characteristics. The surface of SWCNTs was modified by iodonium salt molecules that substantially and permanently improved their electrical conductivity. The addition of pyridinium iodine chloride salt (IPyCl) quadrupled the value of the electrical conductivity of the SWCNT film, which reached values as high as 1022 S cm−1. Subsequently, the electrochemical performance of the newly designed self-standing SWCNTs with deposited IPyCl in aqueous neutral 1 M Li2SO4 and redox-active 1 M KI electrolytes was thoroughly analysed. Because redox activity of iodine species was observed mainly on the positive electrode, activated carbon with a developed surface area was used as a negative electrode to balance the faradaic charge. Due to the notable stability of iodonium salt dopant (instead of labile halogen-containing compounds typically used for SWCNT doping), robust charge/discharge performance of EC was demonstrated (> 10 000 cycles) in Li2SO4 electrolyte. Moreover, a significant improvement of capacitor metrics (from 49 to 75 F g−1) was obtained when electrodes modified by previously unexplored iodonium salt were utilized in 1 M KI electrolyte. Extensive analysis of the obtained data led to the elucidation of the doping mechanism responsible for the aforementioned achievements. The novel SWCNT-based electrodes enhanced with iodonium salt are auspicious materials, which can be used to build EC systems of appreciable capacitance.

Suppressing Ion Migration by Synergistic Engineering of Anion and Cation toward High-Performance Inverted Perovskite Solar Cells and Modules.

Ion migration-induced intrinsic instability and large-area fabrication pose a tough challenge for the commercial deployment of perovskite photovoltaics. Herein, an interface heterojunction and metal electrode stabilization strategy is developed by suppressing ion migration via managing lead-based imperfections. After screening a series of cations and nonhalide anions, the ideal organic salt molecule dimethylammonium trifluoroacetate (DMATFA) consisting of dimethylammonium (DMA+) cation and trifluoroacetate (TFA-) anion is selected to manipulate the surface of perovskite films. DMA+ enables the conversion of active excess and/or unreacted PbI2 into stable new phase DMAPbI3, inhibiting photodecomposition of PbI2 and ion migration. Meanwhile, TFA- can suppress iodide ion migration through passivating undercoordinated Pb2+ and/or iodide vacancies. DMA+ and TFA- synergistically stabilize the heterojunction interface and silver electrode. The DMATFA-treated inverted perovskite solar cells and modules achieve a maximum efficiency of 25.03% (certified 24.65%, 0.1 cm2) and 20.58% (63.74 cm2), respectively, which is the record efficiency ever reported for the devices based on vacuum flash evaporation technology. The DMATFA modification results in outstanding operational stability, as evidenced by maintaining 91% of its original efficiency after 1520 h of maximum power point continuous tracking.

Zinc‐Coordinated Imidazole‐Based Ionic Liquid as Liquid Salt for All‐Temperature Aqueous Zinc‐Ion Batteries

AbstractOwing to the intrinsically high safety, low cost, natural abundance, and high energy density of Zn metal, aqueous Zn ion batteries (AZIBs) have become a promising candidate for large‐scale energy conversion and storage. However, the practical application of AZIBs is hampered by the severe Zn dendrites growth and the poor low‐temperature performance due to the elevated freezing point of aqueous electrolyte. Herein, the study proposes a new kind of room‐temperature liquid Zn salt, which is called Zn coordinated ionic liquid (i.e., (EMIM)5Zn(OTF)7), for all‐temperature AZIBs. The aqueous electrolyte containing 0.261 mol kg−1 (EMIM)5Zn(OTF)7 in Ethylene Glycol (EG) / H2O (6:4) exhibits ultralow freezing point below −100 °C. The liquid Zn salt and EG molecules not only modulate the solvation structure of Zn2+ ion, reducing the coordinated H2O in the first solvation sheath, but also suppresses the parasitic side reaction. As a proof of concept, Zn || Zn symmetric cells and Zn || PANI full cells with the designed electrolyte achieve improved cycling stability and can operate under wide temperature (from −40 to 60 °C). Even with high Zn utilization ratio of 40%, long cycle life over 70 times with capacity retention of 80% is achieved.

Chiral Quaternary Ammonium Salt‐Catalyzed Enantioselective Addition Reactions of Hydantoins

AbstractWe herein report a protocol for the asymmetric 1,4‐addition of hydantoins to various Michael acceptors by utilizing Cinchona alkaloid‐based chiral quaternary ammonium salt catalysts. Various products were obtained with moderate to good enantioselectivities and accompanying computational investigations helped to identify key interactions responsible for the observed selectivity. DFT calculations along with non‐covalent interaction plots reveal the presence of numerous stabilizing non‐classical hydrogen bonding interactions along with other non‐covalent interactions between the chiral quaternary ammonium salt and hydantoin molecule in the C−C bond forming transition states leading to the formation of the products. In addition, a first proof‐of‐concept for an analogous a‐sulfanylation reaction, albeit with poor selectivity, is reported as well.

An efficient strategy for the preparation of a MIL-53(Al)-NH<sub>2</sub> membranes with high ion selectivity and desalination performance

The efficient extraction of sodium (Na<sup>+</sup>) and lithium (Li<sup>+</sup>) from seawater and salt lakes is increasingly demanding due to their great application value in chemical industries. However, coexisting cations such as divalent calcium (Ca<sup>2+</sup>) and magnesium (Mg<sup>2+</sup>) ions are at the subnanometer scale in diameter, similar to target monovalent ions, making ion separation a great challenge. Here, we propose a simple and fast secondary growth method for the preparation of MIL-53(Al)-NH<sub>2</sub> membranes on the surface of anodic aluminum oxide. Such membranes contain angstrom-scale (~7 Å) channels for the entrance of small monovalent ions and water molecules, endowing the selectivities for monovalent cations over divalent cations and water over salt molecules. The resulting high-connectivity MIL-53(Al)-NH<sub>2</sub> membranes exhibit excellent ion separation performance (a selectivity of 121.42 for Na<sup>+</sup>/Ca<sup>2+</sup> and 93.81 for Li<sup>+</sup>/Mg<sup>2+</sup>) and desalination performance (a water/salt selectivity of up to 5196). This work highlights metal-organic framework membranes as potential candidates for realizing ion separation and desalination in liquid treatment.

External electric field driven conformation transition between lithium salts and electride-like molecules: intriguing NLO switches in Li@corannulene.

The external electric field has emerged as a powerful tool for building molecular switches with excellent properties. In this work, we investigate the impact of an external electric field on the transition between lithium salt and electride-like molecule conformations in Li@corannulene. Remarkably, the distance between the Li atom and the corannulene bottom displays a sharp increase under the influence of an external electric field strength of F-z = 110 × 10-4 a.u. As the external electric field strength increases, the Li atom brings about different directions of charge transfer (CT). The natural population analysis (NPA) charge and the molecular electrostatic potential (ESP) results show that the intermolecular CT occurs from the Li atom to the corannulene with the F-z ranging from 0 to 100 × 10-4 a.u. Interestingly, when the external electric field reaches F-z = 110 × 10-4 a.u., the CT is oriented from the corannulene to the Li atom. Moreover, electron localization function (ELF) basins are presented under an F-z of 110 × 10-4 a.u., which indicates that Li@corannulene exhibits electride-like (e-⋯[Li@corannulene]+) molecules and lithiation salt (Li+[corannulene]-) under an F-z of 0 to 100 × 10-4 a.u. Significantly, the differences in charge transfer also contribute to a significant improvement in hyperpolarizabilities (βtot) during the conformation transition from lithiation salt (Li+[corannulene]-) to electride-like (e-⋯[Li@corannulene]+) molecules. This study explores the potential of Li@corannulene as a promising second-order NLO material, and the external electric field provides an efficient strategy for designing and developing NLO switching devices.

Enhanced Charging/Discharging Process in Perovskite Active Light Source for High‐Speed Visible‐Light Communication

AbstractMetal halide perovskites are promising light source materials for visible light communication (VLC) due to their excellent photoelectric properties and small resistance‐capacitance time constant. However, previous reports mainly used perovskites as the passive light sources, which not only makes it susceptible to posterior excitation light sources, but also complex in the integration process. Herein, the quasi‐2D PEA2Csn‐1PbnBr3n+1 perovskite light–emitting diodes (PeLEDs) as an active light source in VLC link is demonstrated. It is found that the charging/discharging process of PeLEDs is an important factor governing the ‐3 dB bandwidth (f‐3 dB) of the VLC. To improve this, 3‐sulfopropyl methacrylate potassium salt (SMPS) molecules are introduced into perovskite to simultaneously passivate deep and shallow energy level defects at grain boundaries. Additionally, the multiple quantum wells structures of PEA2Csn‐1PbnBr3n+1 are modified to be flat. At the optimal SMPS concentration, the maximum external quantum efficiency of PeLEDs reaches 21.5%. Meanwhile, the VLC achieves 3.2 MHz f‐3 dB with data transmission of 18.6 Mbps, which is the highest f‐3 dB in PeLEDs with the same active area. Hence, it provides a versatile method to improve the performance of VLC links based on active light sources and advances toward the goal of high‐speed, energy‐efficient and secure free communication.

Highly Efficient Arginine Intercalated Graphene Oxide Composite Membranes for Water Desalination.

Graphene oxide-based composite membranes have received enormous attention for highly efficient water desalination. Herein, we prepare arginine/graphene oxide (Arg/GO) composite membranes by surface functionalizing GO nanosheets with arginine amino acid. Arginine has a unique combination of hydroxyl and amino functional groups that cross-link GO nanosheets through hydrogen bonding and electrostatic interactions. The as-prepared Arg@GO composite membranes with different thicknesses are used to separate the salt and dye molecules. The 900-nm-thick Arg@GO composite membrane shows high rejection of 98% for NaCl and 99.8% for MgCl2, Ni(NO3)2, and Pb(NO3)2 with good water permeance. Such a membrane also shows a high separation efficiency (100%) for methylene blue, rhodamine B, and Evans blue dyes. At the same time, the ultrathin Arg@GO composite membrane (220 ± 10 nm) exhibits high water permeance of up to 2100 ± 10 L m-2 h-1 bar-1. Furthermore, the 900-nm-thick Arg@GO composite membrane is stable in an aqueous environment for 40 days with significantly less swelling. Therefore, these membranes can be utilized in future desalination and separation applications.

Exploring the structure–property relationship of ethylenediammonium hydrogen phosphite: Insights from XRD, vibrational, DFT, and biological evaluation

The interaction between the molecules of phosphonic acid (H2P(H)O3) and ethylenediamine (NH2CH2CH2NH2) reacts in an aqueous solution and results in the formation of salt molecules with two NH∙∙∙O hydrogen bonds. The calculated stabilization energy of the 1:1 salt molecule, which represents the strength of the two NH∙∙∙O hydrogen bonds, is 8.063 kcal/mol (33.735 kJ/mol). The title compound crystallizes in the centrosymmetric space group Pbca of the orthorhombic system with eight molecules per unit cell. The three-dimensional supramolecular network is formed by hydrogen bonds between every hydrogen atom in both of the NH3+ groups of the ethylenediammonium cation. Hirshfeld surfaces and two-dimensional fingerprint plots were used to analyze the interactions of ethylenediammonium cations and hydrogen phosphite anions forming a three-dimensional supramolecular structure. Practically, two types of interactions, i.e. NH∙∙∙O and H∙∙∙H, are observed for both building units, ethylenediammonium cation and the hydrogen phosphite anion, which cover 100 % of the HS surface of each unit. Density functional theory (DFT) computations of normal mode force constants and structure optimizations were employed to evaluate the molecular structure, fundamental vibrational frequencies, and vibrational band intensities. The utilization of potential energy distribution (PED) allowed for the determination of comprehensive vibrational assignments for the wave numbers. The interactions involving the charge transfers of the supramolecular unit are explained by the computed HOMO and LUMO energy gap of 5.193 eV. To prove that the EDHP has stabilized, NBO analysis has been done. NBO studies establish that strong intra and intermolecular stabilization exists between the ethylenediammonium cation and the hydrogen phosphite anion. Furthermore, to investigate the synthetic chemical EDHP as a possible drug candidate, molecular docking studies and drug-likeness evaluation have been carried out. The best binding energy of the obtained cluster is −3.85 kcal/mol. The rmsd value is found to be 1.950 (≤2 Å) which is fairly good and confirms the best superimposed docked pose. Thus Molecular docking studies reveal that EDHP molecule has a substantial binding affinity for the SARS-CoV-2 protein and can serve as a promising drug candidate. The bioavailability score of 0.55 from pharmacokinetics study suggests that EDHP may have moderate bioavailability.

Electrochemical Properties and Performance of Supersaturated Vanadium (IV) and V(V) Electrolytes

Earlier research has shown that supersaturated vanadium sulfate electrolytes can remain stable for an extended time ranging from hours to days making them suitable for electrochemical energy storage applications. This study investigates the electrochemical characteristics of supersaturated vanadium IV and V sulfate solutions and the solvation structures of molecules in these solutions. The electrochemical characterizations, e.g., OCV, constant current/voltage/overpotential oxidation, and reduction, reveal that supersaturated V(IV) and V(V) solutions contain electrochemically active ions, inactive-but-convertible molecules, and inactive-and-unconvertible molecules. The chemical conversion rate from inactive-but-convertible molecules to active ions is high enough to maintain a constant active ions concentration during the electrochemical reactions. Possible structures and the relationship of these structures to their electrochemical activity at supersaturated levels were discussed. The inactive-but-convertible molecules are suggested to be the agglomerates of the individual dissociated vanadium ion pairs, while the inactive-and-unconvertible molecules consist of undissociated vanadium salt molecules with the sulfate anions bonded directly to the vanadium cations. This work also found that preparation methods (with or without preheating the electrolyte during synthesis) and the oversaturation level can affect the composition of the molecules in the electrolyte.

Efficient and stable perovskite solar cells: The effect of octadecyl ammonium compound side-chain

The extreme vulnerability of hybrid perovskite solar cells (PSCs) to moisture greatly limits the realization of their full potential. Here, we propose an efficient strategy to reinforce the efficiency and the ambient stability of PSCs via employing a series of octadecyl ammonium salts (OASs): octadecyl trimethyl ammonium chloride (OTAC), octadecyl dimethyl benzyl ammonium chloride (ODBAC), and 3-(trimethoxysilyl)propyl octadecyldimethyl ammonium chloride (TOAC), as passivating agents. Among these OASs, TOAC bearing a trimethoxysilane (Si-O-CH3) side chain group most efficiently promoted the efficiency along with the high-humidity stability of PSC devices. TOAC significantly passivated the defects, assisted better energy-level alignment and facilitated charge carrier transport in the devices. The TOAC-passivated PSCs exhibited an increase in the average PCE from 16.62 ± 0.56 % to 20.06 ± 0.68 % with a substantially enhanced fill factor of 80.10 ± 1.82 %. Furthermore, the unencapsulated TOAC-passivated PSCs preserved 90 % of their performance after storage in ambient conditions (25–30 ℃, 50–70 % relative humidity) for 300 h. When no OAS passivator was introduced, the devices were losing more than 74 % of their starting PCE after 150 h. The Si-O-CH3 groups side-chained to the OAS molecules were capable of supporting superior protection to the PSC devices against the permeation of high-moisture. Thereupon, the application of multifunctional octadecyl ammonium salt molecules to passivate defects and tailor the interface energy-level alignment in PSCs offers an encouraging staging to upgrade the PV performance of PSCs.

Interaction between components of polymeric light emitting electrochemical cells: A DFT case study for MDMO-PPV/KCF3SO3/PEO system

Polymer light emitting electrochemical cells (PLECs) are organic electronic devices that define interesting alternatives to organic light-emitting devices. However, despite their potential application, some of the basic operational mechanisms involved in their operation are still not completely understood. In this context, here we report a theoretical attempt to unravel some basic aspects on this subject considering a model system based on poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4- phenylene vinylene] (MDMO-PPV), potassium(I) trifluoromethanesulfonate (KCF3SO3) and polyethylene oxide (PEO). Structural and reactivity properties of the constituents were evaluated via DFT-based electronic structure calculations. Condensed-to-atoms Fukui indexes were estimated via Hirshfeld partition charge to identify preferred sites for PLEC component’s interactions. The results suggest that the presence of ionic salt induces significant changes on the semiconducting polymer’s electronic properties, which are dependent on the number of salt molecules and their oxidation state, influencing the devices’ charge dynamics (injection and transport), reinforcing previous results obtained for other similar systems.

REACTIVITY OF DISUBSTITUED AMMONIUM SELENIATE SALTS WITH SNME3CL. X-RAY STRUCTURE OFCY2NH2SEO4SNME3

The reaction of Cy2NH2HSeO4.H2Oand SnMe3Cl led to the formation of Cy2NH2SeO4SnMe3 (1), which crystallizes in the orthorhombic space group Pbca with Z = 16, a = 11.59430(10) AÌŠ, b = 19.3138(3)AÌŠ, c = 36.8673(6)AÌŠ, and V = 8255.7(2)AÌŠ3. The asymmetric unit consists of two [SeO 4 SnMe 3 ]- in which the SnMe3 residue is trans coordinated. The complex-anion are linked via NH----O hydrogen bonds which are involved by Cy2NH2+cation. From a supramolecular point of view, the superposition of [SeO4SnMe3]- along a axis are linked by the NH---O of Cy2NH2+cation along c axis giving a tridimensional structure. The characterization of 1 is accompanied by infrared and NMR characterization of two seleniate complexes containing SnMe3 residue to complete the study of reactivity between dialkylammonium seleniate salt and SnMe3Cl molecule.

Structural and vibrational characterizations, DFT calculations, second harmonic generation, molecular docking studies on L–argininium 3,3-dimethylacrylate

This study is aimed to understand the structure, stability, and properties of L-argininium 3,3-dimethylacrylate (ADMA) crystals. These single crystals were cultivated through a solution growth method. The structure describes the orthorhombic crystal system with four molecules per unit cell, and crystallizes in a non-centrosymmetric (P212121) space group. A systematic structural analysis of ADMA was carried out using density functional theory (DFT) with a B3LYP/6-31+G* basis set to examine the intra/intermolecular type of bonding interactions, excitation energies, vibrations, and electrostatic interaction between the charged particles. The protonated L-argininium cation and dissociated 3,3-dimethylacrylate anion are joined via N–H⋯O hydrogen bonds with R22(8) to form an asymmetric unit of ADMA. The energy of interaction between l-arginine and 3,3-dimethylacrylic acid molecules was calculated to be 17.95 kcal mol−1 (75.09 kJ mol−1), leading to the formation of a 1:1 salt molecule. Additionally, the Density Functional Theory (DFT) calculations supported the assignment of vibrational bands. The calculated frontier molecular orbital energy gap 4.702 eV indicating the charge transport that happens between the cation and the anion. Furthermore, global chemical reactivity descriptors were calculated. The degree of second harmonic generation response of the orthorhombic phase of ADMA was found to be 0.22 relative to potassium dihydrogen phosphate. In addition, first-order hyperpolarization susceptibility calculations confirm the nonlinear optical activity of the ADMA crystal. The present study also focuses on the anti-breast cancer activity of ADMA using three breast cancer proteins (Protein Data Bank codes: 5NWH, 5NQR, and 1OQA) by molecular docking studies.

Surfactant regulated aggregation-induced emission of tetraphenylethene-based tetracationic salt for the construction of light harvesting supramolecular system

Fluorescence resonance energy transfer (FRET) is an efficient optical molecular scale that has been widely used in many fields, and aggregation-induced emission (AIE) luminescent materials show great potential in constructing FRET systems. In this paper, an efficient supramolecular polymer of AIE was prepared in aqueous solution based on tetraphenylethene-based tetracationic salt molecule (1) with AIE properties, using the hydrophobic effect and electrostatic interaction with sodium dodecyl sulfonate (AS). Then, based on supramolecular aggregate (1-AS) and Rhodamine B (RB) dye, the efficient FRET system was prepared in aqueous solution with 1-AS as energy donor and RB as energy acceptor. The Stokes shift of the system can reach 208 nm, and the fluorescence intensity of RB aqueous solution with the same concentration increased 11.80 times. Moreover, the energy transfer efficiency and the antenna effect value reached 77.5%, 14.3, respectively. The method based on simple AIE donor to achieve efficient luminescence of dye molecules is of great significance for the realization of efficient light-trapping system of aqueous solution in practical applications.

3,5-Lutidine penta-aqua sulfate complexes of first-row transition metals: [M(3,5-lutidine)(H2O)5]SO4, with M = Mn, Co, Ni, and Zn.

The reactions of MnSO4·H2O, CoSO4·7H2O, NiSO4·6H2O and ZnSO4·7H2O with 3,5-lutidine (3,5-di-methyl-pyridine) yield crystals of penta-aqua-(3,5-di-methyl-pyridine-κN)manganese(II) sulfate, [Mn(C7H9N)(H2O)5]SO4, (1), penta-aqua-(3,5-di-methyl-pyridine-κN)cobalt(II) sulfate, [Co(C7H9N)(H2O)5]SO4, (2), penta-aqua-(3,5-di-methyl-pyridine-κN)nickel(II) sulfate, [Ni(C7H9N)(H2O)5]SO4, (3), and penta-aqua-(3,5-di-methyl-pyridine-κN)zinc(II) sulfate, [Zn(C7H9N)(H2O)5]SO4, (4), which were characterized by single-crystal X-ray diffraction. The four crystals are isostructural, demonstrating near identical unit-cell parameters and atomic positions. The metal atoms are all octa-hedrally coordinated, with one lutidine ligand and five water ligands. The sulfate dianion hydrogen bonds with the coordinated water mol-ecules of the dicationic metal complex salts, generating infinite three-dimensional networks.