3D Supramolecular Network Research Articles

Topological Co(II)-Malonate Polymorph: Degradation Properties of Naproxen and Colorimetric Recognition of Acetone, Cr2O72−, and Fe3+

Two Co(II)coordination polymers namely, [Co(mal)(4,4`-bpy)0.5 (H2O)]n(1) and [Co(mal)(4,4`-bpy)0.5 (H2O)]n(2)are synthesized at ambient temperature, both complexes are based on {Co(RCOO)2}unitserving as 3D network along with sqc and fes topology and corroborated by many analytical techniques. CPs(1) crystallized in a 2D manner and then constructed a 3D hydrogen bonding network which was demonstrated monoclinic crystal system while(2)is a 3D supramolecular network that possesses a tetrahedral crystal system, according to topological analysis CPs(1) shows 5-C net and CPs(2) elaborates a 3-C net which proves both are completely different. A luminescence investigation was performed using both coordination polymers (CPs), which demonstrated effective colorimetric detection of acetone, Cr₂O₇²⁻, and Fe³⁺, with corresponding detection limits of 1.91, 2.57, and 0.29 ppm, respectively, in an ethanolic medium. Additionally, the catalytic degradation of Naproxen was evaluated for both catalysts, revealing significant degradation efficiencies of 90% for catalyst (1) and 38% for catalyst (2).

Supramolecular Polymerization of Pseudo[2]rotaxanes Formation of per‐Imidazole Pillar[5]arene‐based Host–Guest Complexations and Halogen Bonding Interactions

AbstractIn this study, we reported the construction of 3D supramolecular polymeric networks using per‐imidazole pillar[5]arene (DIMP5) as a host and 1,4‐diiodotetrafluorobenzene (L) as a halogen bond donor in chloroform. The supramolecular polymerization process was characterized by 1H NMR, 19F NMR spectroscopy, and X‐ray single crystal analysis. The C─I⋯N distance (2.78 Å) and C─I⋯N angle (177°) clearly indicated the formation of halogen bonds in the crystal structure. Meanwhile, by introducing adiponitrile (G) as the guest, a supramolecular polymerization of pseudo[2]rotaxanes was also prepared, which was driven by DIMP5‐based host–guest complexations and halogen bonding interactions.

Synthesis, structural characterization, water ad‐/de‐sorption isotherm, and CO2 uptakes of a 2D Cu(I) metal organic framework with 1,3,5‐tris(4‐pyridylethynyl)benzene (L) and Tricyanomethanide (tcm−) ligands

AbstractA d10 Cu(I) two‐dimensional (2D) metal–organic framework (MOF) with chemical formulas, {[Cd(L)(tcm)(H2O)]⋅2H2O}n (1) (L = 1,3,5‐tris(4‐pyridylethynyl)benzene; tcm−1 = tricyanomethanide) was synthesized and structurally characterized by single crystal X‐ray diffraction method. In 1, the coordination geometry of Cu(I) ion is distorted tetrahedral coordinated to four N atoms from three L and one tcm− ligands. A 2D puckered honeycomb‐like layer is formed via the bridges of Cu(I) ions and L ligands with tris‐monodentate coordination mode. Two 2D layers are mutually interpenetrated via the π–π stacking interaction between benzene ring of L ligand and pyridyl ring of neighboring L ligand to form a two‐fold interpenetrated 2D net and then arranged orderly to construct its 3D supramolecular network. Thermal stability and in‐situ temperature‐dependent structural variations of 1 are performed by TG analysis associated with temperature‐dependent PXRD measurement. The water vapor ad‐/de‐sorption isotherm and CO2 adsorption isotherm of 1 are measured and discussed.

The Role of Alkyl Chains in the Thermoresponse of Supramolecular Network.

Supramolecular materials provide a pathway for achieving precise, highly ordered structures while exhibiting remarkable response to external stimuli, a characteristic not commonly found in covalently bonded materials. The design of self-assembled materials, where properties could be predicted/design from chemical nature of the individual building blocks, hinges upon ourability to relate macroscopic properties to individual building blocks - a feat which has thus far remained elusive. Here, a design approach is demonstrated to chemically engineer the thermal expansion coefficient of 2D supramolecular networks by over an order of magnitude (\boldmath 120 to \boldmath 1000 × 10-6K-1). This systematic study provides a clear pathway on how to carefully design the thermal expansion coefficient of a 2D molecular assembly. Specifically, a linear relation has been identified between the length of decorating alkyl chains and the thermal expansion coefficient. Counter-intuitively, the shorter the chains the larger is the thermal expansion coefficient. This precise control over thermo-mechanical properties marks a significant leap forward in the de-novo design of advanced 2D materials. The possibility to chemically engineer their thermo-mechanical properties holds promise for innovations in sensors, actuators, and responsive materials across diversefields.

Unveiling Heterogeneous Catalytic Potential of Distinctly Coordinated Polymers Toward Henry and Morita‐Baylis‐Hillman Reactions

AbstractThree 1D coordination polymers (CPs), {[CuL2(H2O)] ⋅ (H2O)3}n (1) {[CoL2(H2O)2] ⋅ (H2O)}n (2) and {[NiL2(H2O)] ⋅ (H2O)3}n (3), (L1=N‐nicotinoylglycinato) have been synthesized by adopting a solvothermal reaction strategy and characterized through several spectral techniques i. e., elemental analyses, FT‐IR, TGA, EDX, DSC, AAS, and PXRD. X‐ray single crystal analysis revealed the 5‐, 6‐ and 7‐coordinated structures respectively for CPs 1, 2 and 3 wherein, L1 connects the metal ions in a bridging mode. The CPs entail H‐bonding, π–π stacking along with other non‐covalent interactions and expand into 3D supramolecular networks. Further, FESEM and HRTEM provided morphological insight for 1–3 and aid in obtaining interplanar spacings. CPs 1–3 possessing distinct coordination numbers and good thermal stability have been subjected to catalysis after optimization and notably, these serve as efficient, easy to work up, and reusable porous heterogeneous catalysts for Henry and Morita‐Baylis‐Hillman (MBH) reactions with reasonably good yields (97–93 %). Remarkably, catalyzed by 1–3 can be reused at least seven times for the Henry reaction and six times for the MBH reaction, retaining their catalytic efficiency. Relative catalytic efficacy toward the Henry and MBH reactions follows the order 1>2>3. Present findings are based on a rational approach of varying coordination number (5, 6 and 7) and metal ions [Cu(II), Co(II) and Ni(II)] respectively in 1–3 having structural evidence and examine their catalytic performances for typical Henry and MBH reactions.

Multi-Modal Sensing Ionogels with Tunable Mechanical Properties and Environmental Stability for Aquatic and Atmospheric Environments.

Ionogels have garnered significant interest due to their great potential in flexible iontronic devices. However, their limited mechanical tunability and environmental intolerance have posed significant challenges for their integration into next-generation flexible electronics in different scenarios. Herein, the synergistic effect of cation-oxygen coordination interaction and hydrogen bonding is leveraged to construct a 3D supramolecular network, resulting in ionogels with tunable modulus, stretchability, and strength, achieving an unprecedented elongation at break of 10800%. Moreover, the supramolecular network endows the ionogels with extremely high fracture energy, crack insensitivity, and high elasticity. Meanwhile, the high environmental stability and hydrophobic network of the ionogels further shield them from the unfavorable effects of temperature variations and water molecules, enabling them to operate within a broad temperature range and exhibit robust underwater adhesion. Then, the ionogel is assembled into a wearable sensor, demonstrating its great potential in flexible sensing (temperature, pressure, and strain) and underwater signal transmission. This work can inspire the applications of ionogels in multifunctional sensing and wearable fields.

C–H···I assisted 2D Cd(II)-coordination polymer: Remarkable photocatalytic degradation of rose bengal dye and efficient colorimetric recognition of La3+, and ClO4-

In this work, we report the effective synthesis, by use of solvothermal procedures, of a new coordination polymer, [CdI2(DPP)]n (1), where DPP stands for 1,3-Di(4-pyridyl)propane. The structural characteristics of [CdI2(DPP)]n (1) were analysed utilizing a variety of analytical techniques, including SCXRD, FT-IR, TGA, SEM-EDAX, elemental mapping analysis and powder X-ray diffraction. Our results showed the existence of a 2D supramolecular network created by hydrogen bonding interactions between C4–H4—-I2 and a 1D coordination polymeric chain. The [CdI2(DPP)]n (1) network has promising luminous sensing properties toward inorganic anions and metal cations with quenching efficiencies 96.89 % and 95.51 % for La3+ and ClO4− respectively. Moreover, [CdI2(DPP)]n (1) achieves an exceptional degradation efficiency of 97.3 % when used as a photocatalytic degradant of the potentially hazardous organic dye Rose Bengal, outperforming other dyes in this regard. Hence, this new coordination polymer holds significant promise for applications in sensing and environmental remediation.

Superamphiphilic aerogels with 2D lamellar structure of gelatin-tuned 3D supramolecular network of collagen fibers for high-performance separation of surfactant-stabilized emulsified oily wastewater

Superwetting aerogel is a promising alternative for the remediation of emulsified oily wastewater for its high porosity combined with extreme wettability enabled high separation performances to emulsion wastewater. However, it remains challenging for superwetting aerogels to accomplish high-performance dual separation to surfactant-stabilized oil-in-water (O/W) and water-in-oil (W/O) emulsions with high stability. Herein, an environmentally benign superamphiphilic composite aerogel was prepared by a green synthesis route that relied on the utilization of natural amphiphilic biomass. Collagen fibers (CFs) were utilized to construct the three-dimensional (3D) supramolecular skeleton of aerogel to provide high storage capacity of water/oil and outstanding capillary effect to boost the mass transfer. The two-dimensional (2D) lamellar structure of gelatin (Gel) was further grown on the skeleton of CFs aerogel to play the role for simultaneously enhanced demulsifying capability and spreading of emulsions. The as-prepared superamphiphilic aerogel enabled the separation of highly stable surfactant-stabilized O/W and W/O emulsions with high separation efficiency and flux. Excellent recycling performances and anti-fouling performance were also confirmed. Our investigations therefore demonstrated that the structural engineering of superamphiphilic aerogel is a promising way to realize high-performance dual separation of surfactant-stabilized O/W and W/O emulsion wastewater.Graphical

Synthesis, Characterization, and Application of a Polyoxometalates‐Based CuII Complex for Efficient Catalytic Oxidation and Electrochemical Detection

AbstractThe development of eco‐friendly, high‐efficiency polyoxometalates (POMs) catalysts is vital for advancing catalytic oxidation and electrochemical detection in environmental protection. Herein, a POM‐based CuII‐containing complex with the molecular formula [H(4‐AP)]8[Cu2(H2O)4(P2Mo5O23)2]·8H2O (1) (4‐AP = 4‐aminopyridine) is synthesized using the hydrothermal method, and the crystal structure is determined by single X‐ray diffraction (SXRD), infrared (IR) spectroscopy, and powder X‐ray diffraction (PXRD). Structurally, complex 1 exhibits a one dimension (1D) chain arrangement, composed of CuII ions and Strandberg‐type (P2Mo5O23)6− anionic clusters. These 1D chains are further interconnected through [H(4‐AP)]+ ligands, resulting in the formation of a two dimension (2D) supramolecular network. Complex 1 serves as an outstanding heterogeneous catalyst for the oxidation of methyl phenyl sulfide (MPS), demonstrating a remarkable conversion rate of 99% for MPS and a selectivity of 98% toward methyl phenyl sulfoxide (MPSO). In addition to its catalytic capabilities, complex 1 is also employed in the electrochemical detection of FeIII and CrVI ions, with low limits of detection (LODs) at 4.92 µm for FeIII and 7.82 µM for CrVI.

1D heteronuclear coordination polymers of hexacyanocobaltate(III) with 2-hydroxymethylpyridine

Three new hexacyanocobaltate(III) complexes, {[M2(hmpy)4Co(µ-CN)4(CN)2]∙2H2O}n (M = Cu(II) (1), Zn(II) (2) and Cd(II) (3)) were synthesized with 2-hydroxymethylpyridine (hmpy) ligand, and characterized by vibration (FT-IR and Raman) spectral, single crystal X-ray diffraction (SC-XRD) and powder X-ray diffraction (PXRD), thermal and elemental analyses techniques. The crystallographic analyses revealed that cyanide complexes 1–3 are infinite one-dimensional coordination polymers. Each M ion is coordinated by two nitrogen and two oxygen atoms from the hmpy ligands and two nitrogen atoms from the cyanide ligands, displaying a distorted octahedral coordination geometry. Similarly, each Co(III) ion is coordinated by six carbon atoms from cyanide ligands to form a distorted octahedral coordination geometry. These complexes form 3D supramolecular networks through OH···O hydrogen bonds and CH···N interactions. Additionally, structural analyses such as metal salts, pH values of the compounds obtained under different conditions were evaluated. A synthesis-structural analyses relation was made from these data.

Two Zn(II) complexes based on bis(benzimidazole) and different dicarboxylate anions: synthesis, structures, and fluorescent properties

Two new zinc(II) complexes, [Zn2(PBM)2(terephthalate)(formate)2] (1) and {[Zn(PBM)(fumarate)]∙H2O}n (2), were synthesized using 1,3-bis(1H-benzo[d]imidazol-2-yl)propane (PBM) and two different dicarboxylic acids under solvothermal conditions. Complexes 1 and 2 have been characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction analysis. The structural analysis showed that 1 was a binuclear structure and then formed a 3D supramolecular network structure through hydrogen bond and π-π conjugation, while 2 was a one-dimensional coordination polymer. In 1 and 2, the zinc ions were four-coordinate with an N2O2 donor set and a slightly distorted tetrahedral geometry. The solid-state fluorescence properties indicate that the fluorescence peaks belong to the π*-π transition of the ligand PBM, which has a significant red shift and enhancement with the order being 1 > 2 > PBM. The stronger fluorescence of the complexes than the ligand is due to the immobilization of the ligand through coordination, which reduces the energy loss of thermal vibration. The π∙∙∙π conjugation in 1 results in a stronger fluorescence of 1 than 2. Therefore, coordination and π∙∙∙π conjugation will affect the fluorescence of complexes.

New in situ generated acylhydrazidate-coordinated complexes: Syntheses, structural characterizations and magnetic properties

The present study reports the successful synthesis of three new magnetic coordination polymers, namely [Mn(BPTH)(H2O)]n (1), [Co(BPTH)(phen)]n (2), and [Co(BPTA)(phen)(H2O)2]n (3), through a solvothermal method (H2BPTH = biphenyl-3,3′,4,4′-tetracarboxyhydrazide, H2BPTA = biphenyl-3,3′,4,4′-tetracarboxylic acid, phen = 1,10-phenanthroline). In compounds 1 and 2, the bishydrazide ligand H2BPTH is formed by in situ acylation of H2BPTA with hydrazine hydrate. All the three title compounds contain M2O2 clusters (M=Mn(1), Co(2) and Co(3)). In compound 1, the amido-oxygen atoms O1 coordinate with Mn2+ to form a Mn2O2 cluster, while the adjacent Mn2O2 cluster is interconnected by the ligand's oxygen atoms O3 and O4, resulting in an infinite expansion into a 3D network structure. Compound 2 exhibits a 1D chain structure containing Co2O2 clusters, which further extends into a 2D supramolecular layer through π···π stacking interactions. Compound 3 comprises adjacent Co2O2 clusters interconnected by oxygen atoms O1, O2, and O5 on the ligand to form a 2D layered architecture. The 2D layers are linked through intermolecular O–H···O hydrogen bonds of H2BPTA ligands to form a 3D supramolecular network. Magnetic measurements reveal weak ferromagnetic behavior for compound 1 while compounds 2 and 3 exhibit weak antiferromagnetic interactions at different temperatures. Overall, this research presents new insights into the design and synthesis of coordination polymers with diverse structures and magnetic properties.

Syntheses and photochemically antibiotic degradation of two Co(II)-based coordination polymers

Two new Co(II)-based coordination polymers (CPs), designated as [Co2(bbp)4(1,3-bdc)4]n(1) and [Co(bbp)3(NO3)2(H2O)]n(2) (bbp = 3,5-bis(benzoimidazo-1-ly) pyridine; 1,3-H2bdc = 1,3-benzenedicarboxy acid), were synthesized using a dual ligand approach. The characterization of these CPs involved single- crystal -XRD, UV–visible, FT-IR, and TGA analysis. Both CPs 1 and 2 exhibit a distorted octahedral geometry. Both 1 and 2 show a 1D ladder chain, and this chain-like structure undergoes further development into a more intricate two-dimensional (2D) supramolecular network. The thermal stability analysis revealed that 1 and 2 are stable at temperatures of 119 °C and 286 °C, respectively, with no significant mass loss. Notably, both CPs displayed semiconducting properties. The photocatalytic degradation capabilities of CPs 1 and 2 were investigated against antibiotics such as metronidazole (MDZ), Tinidazole (TDZ), ornidazole (ODZ), and furazolidone (FZD). CP 1 exhibits exceptional photocatalytic activity against FZD. A dosage of 5 mg/L of CP 1 resulted in a remarkable degradation efficiency of 92.2 % for 40 ppm FZD. Additionally, a proposed photodegradation mechanism was investigated through radical trapping experiments.

Two luminescent d10 metal coordination polymers for selective and sensitive detection of Hg2+ ions and pefloxacin in aqueous solution

Detection of heavy ions and antibiotics employing fuorescent sensing techniques has been one of the most active research fields in chemistry. Based on 1,3-bis(2-ethylbenzimidazol-1-ylmethyl)benzene (L) and 2,5-dichloroterephthalic acid (H2DCTP) mixed ligands, two new coordination polymers [Cd2L(DCTP)2·H2O]n (1) and [ZnL(DCTP)]n (2) were synthesized by changing the metal ions under solvothermal conditions. 1 expresses a double-layer V-shaped 1D chain, which further extended into a 2D supramolecular network through classic O–H⋯O hydrogen bonding interactions. 2 features a 2D 4-connected sql layer. The two CPs perform high thermal and pH stability. 1 and 2 are the first CPs to detect Hg2+ ions and pefloxacin by fluorescence quenching with low detection limits and superior recyclability.

Structural elucidation and interpretation of 2D‒3D supramolecular assemblies featuring lone-pair···π interaction in two Cu(II)‒PDA complexes: Experimental and computational assessment

The structural study of two synthesized Cu-PDA (Cu = Copper(II), PDA = deprotonated Pyridine-2,6-dicarboxylic acid) complexes has been carried out using single-crystal X-ray diffraction where complex (1) [Cu(PDA)(H2O)2] exhibits one-dimensional (1D) and two-dimensional (2D) supramolecular assemblies and complex (2) [Cu(PDA)(H2PDA)]·H2O exhibits 1D, 2D, and 3D (three-dimensional) supramolecular networks in their solid-state structure with the aid of intermolecular noncovalent interactions. Lone pair···π/π···lone pair networks are exclusively found in both complex (1) and (2). The intermolecular interactions are characterized through Hirshfeld surface analysis and quantified by 2D fingerprint plot. The noncovalent interactions are further characterized by Bader's theory of ‘Atoms in Molecules’ (AIM) and ‘noncovalent interaction’ (NCI) plot and the topological parameters at bond critical points (BCPs) have been evaluated. Therefore, the energetic factors to the stabilization of the crystal structure observed experimentally have been obtained by the computational calculations.

Supramolecular complexes of Co(II), Zn(II) and Mn(II) based on a pyridazine dicarboxylic derivative: Synthesis, crystal structures and properties

Three supramolecular complexes of Co(II), Zn(II) and Mn(II) based on a pyridazine dicarboxylic derivative, namely, {M(H2O)2[H(4-CPCA)]2}·2H2O (M = Co (SNUT-16), Zn (SNUT-17), Mn (SNUT-18), H2(4-CPCA) = 1-(4-carboxyphenyl)-4-oxo-1,4-dihydropyridazine-3-carboxylic acid, have been successfully obtained by the solvothermal method. Single crystal X-ray crystallography reveals that SNUT-16, SNUT-17 and SNUT-18 are isostructural, which exhibit same 3D supramolecular network. Density Functional Theory (DFT) calculations were carried out to ascertain the optimum geometry structures of three complexes with the DFT/B3LYP method at the 6–311Gcomputational level and the calculated HOMO and LUMO energies were presented. Theoretical modeling on the electronic structure properties was performed, quantitative analysis of intermolecular interactions in crystal structures has been conducted using Hirshfeld surface analysis. In addition, the fluorescence, molecular docking and antibacterial properties also had been investigated at room temperature.

Bifurcated Polymorphic Transition and Thermochromic Fluorescence of a Molecular Crystal Involving Three-Dimensional Supramolecular Gear Rotation.

The ability of molecules to move and rearrange in the solid state accounts for the polymorphic transition and stimuli-responsive properties of molecular crystals. However, how the crystal structure determines the molecular motion ability remains poorly understood. Here, we report that a three-dimensional (3D) supramolecular gear network in the green-emissive polymorph 1G of a dialkylamino-substituted anthracene-pentiptycene π-system (1) enables an unusual bifurcated polymorphic transition into a yellow-emissive polymorph (1Y) and a new green-emissive polymorph (1G*) via 3D correlated supramolecular rotation. The 90° forward correlated rotation causes the molecular conformation between the octyl and the anthracene units to change from syn to anti, the ladder-like supramolecular columns to constrict, and the gear network to disengage. This cooperative molecular motion is marked by the gradual formation of an intermediate state (1I) across the entire crystal from 170 to 230 °C, which then undergoes bifurcated (forward or backward rotation) and irreversible transitions to form polymorphs 1Y and 1G* at 230-235 °C. Notably, 1G* is similar to 1G but lacks gear engagement, preventing its transformation into 1Y. Nevertheless, 1G can be restored by grinding 1Y or 1G* or fuming with dichloromethane (DCM) vapor. This work illustrates the correlation between the crystal structure and solid-state molecular motion behavior and demonstrates how a 3D molecular gear system efficiently transmits thermal energy to drive the polymorphic transition and induce fluorochromism through significant conformational and packing changes.

Synthesis, structural characterization and antitumor activities of manganese and cobalt isothiocyanate complexes with 2,2’-bipyridine

[Mn(SCN)2(2,2′-bipy)2] (1) and [Co(SCN)2(2,2′-bipy)2] (2) were synthesized at ambient temperature by adding aqueous solutions of manganese(II) or cobalt(II) chloride hydrate to aqueous acetonitrile solutions of 2,2′-bipyridine (2,2′-bipy) and potassium thiocyanate. Elemental analyses, FT-IR and UV–vis spectra were used to characterize 1 and 2. Single crystal X-ray diffraction was used to analyze the crystal structures of 1 and 2, revealing that the two are structurally similar. The molecular structures of 1 and 2 consist of Mn or Co ion chelated by two molecules of 2,2′-bipy through four nitrogen atoms and two NCS anions, giving distorted octahedral geometries. The isothiocyanate group is not bridging, instead, two ligands coordinate in a cis arrangement to the manganese or cobalt center by their nitrogen atoms while the sulfur atoms are free. Through hydrogen bonding and π–π stacking interactions, the discrete units of 1 and 2 extend to 3D supramolecular networks with flower and fishbone-like structures. The luminescence behavior of 2,2′-bipy, 1 and 2 were investigated. On HepG2 (liver) and MCF-7 (breast) cancer cells, the anticancer effects of 1 and 2 were evaluated. The activity of 1 and 2 on MCF-7 is more significant than that of HepG2. The IC50 of 1 was lower in HepG2 and MCF-7 cells than for 2.

Novel biologically active paddlewheel-like palladium thiocyanate complex catalyzed cyanation of alkyl bromide utilizing Q-tube system: A green perspective

A novel paddlewheel-like complex of [Pd(SCN)2(3-Acpy)2], (1) was produced at ambient temperature by adding an aqueous solution of palladium chloride to an aqueous acetonitrile solution of 3-acetylpyridine (3-Acpy) and potassium thiocyanate. Elemental analysis, Fourier-transform infrared (FT-IR), ultraviolet–visible (UV–vis), and nuclear magnetic resonance (NMR) spectroscopic methods were used to characterize complex 1 comprehensively. Single crystal X-ray diffraction was used to analyze the crystal structure of complex 1. The palladium atom is bonded to two 3-Acpy ligands and two thiocyanates groups in trans mode giving square planer geometry in complex 1. The discrete units of paddlewheel-like complex 1 through hydrogen bonding extend to form a 3D supramolecular network structure. The synthesized and characterized new palladium complex 1 was utilized as a precatalyst for the cyanation of alkyl bromide using potassium ferrocyanide as a benign cyanide source reagent. The suggested catalytic test reaction under high-pressure conditions via a Q-tube system in green solvent cyclopentyl methyl ether introduced high yields and a short reaction time. Moreover, the cytotoxic activity of complex 1 was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against HePG-2 of liver cancer and MCF7 of breast cancer cell lines. According to the findings, complex 1 has significant strong activity against the cancer cell lines HePG-2 and MCF-7. Additionally, the luminescence spectra of complex 1 were investigated.

Rational Design of 2D Supramolecular Networks Switchable by External Electric Fields.

The reversible formation of hydrogen bonds is a ubiquitous mechanism for controlling molecular assembly in biological systems. However, achieving predictable reversibility in artificial two-dimensional (2D) materials remains a significant challenge. Here, we use an external electric field (EEF) at the solid/liquid interface to trigger the switching of H-bond-linked 2D networks using a scanning tunneling microscope. Assisted by density functional theory and molecular dynamics simulations, we systematically vary the molecule-to-molecule interactions, i.e., the hydrogen-bonding strength, as well as the molecule-to-substrate interactions to analyze the EEF switching effect. By tuning the building block's hydrogen-bonding ability (carboxylic acids vs aldehydes) and substrate nature and charge (graphite, graphene/Cu, graphene/SiO2), we induce or freeze the switching properties and control the final polymorphic output in the 2D network. Our results indicate that the switching ability is not inherent to any particular building block but instead relies on a synergistic combination of the relative adsorbate/adsorbate and absorbate/substrate energetic contributions under surface polarization. Furthermore, we describe the dynamics of the switching mechanism based on the rotation of carboxylic groups and proton exchange, which generate the polarizable species that are influenced by the EEF. This work provides insights into the design and control of reversible molecular assembly in 2D materials, with potential applications in a wide range of fields, including sensors and electronics.