Zigzag Topology Research Articles

Cryoelectron tomography reveals the multiplex anatomy of condensed native chromatin and its unfolding by histone citrullination

Nucleosome chains fold and self-associate to form higher-order structures whose internal organization is unknown. Here, cryoelectron tomography (cryo-ET) of native human chromatin reveals intrinsic folding motifs such as (1) non-uniform nucleosome stacking, (2) intermittent parallel and perpendicular orientations of adjacent nucleosome planes, and (3) a regressive nucleosome chain path, which deviates from the direct zigzag topology seen in reconstituted nucleosomal arrays. By examining the self-associated structures, we observed prominent nucleosome stacking in cis and anti-parallel nucleosome interactions, which are consistent with partial nucleosome interdigitation in trans. Histone citrullination strongly inhibits nucleosome stacking and self-association with a modest effect on chromatin folding, whereas the reconstituted arrays undergo a dramatic unfolding into open zigzag chains induced by histone citrullination. This study sheds light on the internal structure of compact chromatin nanoparticles and suggests a mechanism for how epigenetic changes in chromatin folding are retained across both open and condensed forms.

Linear versus Bent 3d/4f-Heterometallic Clusters: The Carboxylate Effect on the Metal Topology and Magnetic Properties of Two {MnIII2Dy2} Complexes Supported by N-Naphthalidene-o-Aminophenol

The initial use of N-naphthalidene-o-aminophenol (naphH2) chelate in heterometallic cluster chemistry has provided access to two chemically similar but structurally dissimilar [MnIII2Dy2(OMe)2(O2CR)6(naph)2] (R = Me (1), Ph (2)) compounds with rare linear (1) and zigzag (2) topologies, respectively, depending only upon the ancillary carboxylate groups. The “twisted” or “bent”-like structure of 2 has mostly altered the DyIII coordination geometry (square antiprismatic vs triangular dodecahedral in 1), resulting in a slight differentiation of the magnetic dynamics of 2 in comparison with 1. Direct-current (dc) magnetic susceptibility measurements revealed the presence of predominant antiferromagnetic exchange interactions within 1 and 2, while both {MnIII2Dy2} clusters exhibit out-of-phase (χ″Μ), frequency-dependent tails of signals in zero external dc field, characteristic of the onset of the quantum tunneling of magnetization. Attempts to suppress the tunneling through the application of an external dc field were unsuccessful for a wide range of applied fields and alternating-current (ac) frequencies. The combined results demonstrate the ability of the naphH2/RCO2– “blend” of ligands to yield new heterometallic cluster compounds with appealing structural motifs and potentially interesting magnetic properties.

Anion Influence on Supramolecular Interactions in Exo-Coordinated Silver(I) Complexes with N2O2 Schiff Base Macrocycle

Silver(I) complexes with aza-oxa macrocyclic Schiff bases L (L = 1,5-diaza-2,4:7,8:16,17-tribenzo-9,15-dioxa-cyclooctadeca-1,5-dien) were prepared by the reaction of the corresponding macrocycle with four different silver salts (AgX; X = ClO4, PF6, SbF6 and BF4). In all four compounds, silver ions are exo-coordinated by two neighboring ligand molecules in linear and T-shaped geometries. Such a coordination mode results in the formation of infinite 1D polymeric chains. Compounds AgLClO4 and AgLBF4 are isostructural, and polymeric chains display 1D zigzag topology. In AgLPF6 there are three symmetrically unique Ag ions in the asymmetric unit of the compound. Two silver ions are linearly coordinated with two neighboring ligand molecules and are part of a discrete polymer chain. The third silver ion is coordinated with two ligand molecules and a methanol molecule in a T-shaped geometry. Such coordination geometry results in the formation of two discrete infinite polymer chains in the crystal structure. In the AgLSbF6 compound, the chain topology is a linear zigzag chain, but in this compound, there is a difference in the orientation of the Ag-N bond. The Ag-N-Ag bonds are in the trans position relative to the plane calculated through the ligand molecule, while the Ag-N bonds are in the cis position in all other compounds. Due to the presence of a bulky SbF6 anion, the ligand molecule is planar compared to other compounds. Considering intermolecular interactions, there is a huge variety of different interactions, mostly depending on the type of anion. A general supramolecular motif in all compounds is best described as 2D sheets of ligand–metal polymers with anions and solvent molecules sandwiched between them. In addition, the obtained compounds were characterized by IR spectroscopy and thermal analysis. The TG analysis indicates a rather surprising and considerable thermal stability of the prepared compounds, with some compounds thermally stable over 300 °C.

Broadband manipulation of flexural waves based on phase-modulated elastic metasurfaces

As an innovative planar artificial structure, elastic metasurface exhibits great potential in the application fields of vibration and noise control. By virtue of the superior performance of compact/ultra-thin configuration, easy-fabrication and richer physics, metasurfaces are expected to make up for the deficiency of traditional metamaterials. However, achieving broadband exotic elastic-wave manipulations by using metasurfaces remains a highly desired feature. Here, on basis of a classical zigzag topology, we developed various elastic metasurface designs for broadband flexural wave tailoring at a sub-wavelength scale. By tuning the gradient phase shift, a series of extraordinary wavefront manipulation phenomena have been realized, including anomalous refraction, energy focusing, source transformation and self-accelerating beam. Remarkably, numerical and experimental results show that this design possesses absolute advantages of broadband, compact and high efficiency compared with the locally resonant strategy. This work may offer more thriving avenues for vibration and noise control in advanced structures.

High performance of homo-metallic tetracyanonickelate based coordination polymer towards water oxidation electrocatalysis

The search of proficient, copious, economical and robust electrocatalyst is of prime prerequisite. Recently, the usage of cyanometallate based coordination polymers as electrocatalysts for water oxidation has acquired an expanding measure of attraction attributable to their high surface area and stability. In this study, a homo-metallic Ni based cyanometallate coordination polymer [{NiII(4,4ʹ-dipy)4}{Ni(CN)4}]n·(4,4ʹ-dipy)·3H2O·C2H6O2 (1) (4,4ʹ-dipy = 1,3-di(4-pyridyl)propane) is presented as an efficacious and robust electrocatalyst towards water oxidation reaction at pH = 13. The inimitable 3-D zig-zag topology of 1 has directed to ~28 times enhanced surface concentration (Γ) i.e. 39.5 nmol/cm2 as compared to the reported CoFe(CN)6 (Γ = 1.4 ± 0.2 nmol/cm2). The 1 presents a TOF of 0.25 s−1 at an overpotential (η) of 381 mV (vs. RHE) which is much larger than those reported for other cyanide bridged and Ni based coordination polymers for instance: CoFe(CN)6 (TOF = 2 × 10−3 s−1, η = 300 mV), CoFe(CN)5-PVP (TOF = 2 × 10−3 s−1, η = 284 mV), Codca2 (TOF = 2 × 10−3 s−1, η = 358 mV), Ni-UMOFNs (TOF = 0.18 s−1, η = 300 mV), bulk NiCo-MOFs (TOF = 0.15 s−1, η = 300 mV) and Ni-MOF/NF (TOF = 0.25 s−1, η = 400 mV).The overpotential (η) of of 315 mV is required to produce a current density (J) of 1 mA/cm2. Controlled potential electrolysis (CPE), PXRD and FT-IR experiments confirm that 1 remains active and chemically integrate over a 36,000 s test reaction. The outcomes of the comprehensive electrochemical investigations are prophesied to direct the imminent development in designing noble metal free, efficient and low-priced electrocatalysts for oxygen evolution reaction.

Catena-Poly[[(2,2'-bi-pyridine-κ2 N,N')manganese(II)]-di-μ-bromido

In the polymeric title complex, [MnBr2(C10H8N2)] n , the MnII ion, situated on a twofold axis of symmetry, is six-coordinated in a distorted octa-hedral coordination geometry defined by two N atoms from the chelating 2,2'-bi-pyridine ligand and four bridging Br- anions. The crystal reveals a one-dimensional Br-bridged chain along the c-axis direction with a zigzag topology. In the crystals, contacts between chains include π-π inter-actions between pyridyl rings [inter-centroid separation = 4.082 (1) Å].

Ultrahigh-yield on-surface synthesis and assembly of circumcoronene into a chiral electronic Kagome-honeycomb lattice.

On-surface synthesis has revealed remarkable potential in the fabrication of atomically precise nanographenes. However, surface-assisted synthesis often involves multiple-step cascade reactions with competing pathways, leading to a limited yield of target nanographene products. Here, we devise a strategy for the ultrahigh-yield synthesis of circumcoronene molecules on Cu(111) via surface-assisted intramolecular dehydrogenation of the rationally designed precursor, followed by methyl radical-radical coupling and aromatization. An elegant electrostatic interaction between circumcoronenes and metallic surface drives their self-organization into an extended superlattice, as revealed by bond-resolved scanning probe microscopy measurements. Density functional theory and tight-binding calculations reveal that unique hexagonal zigzag topology of circumcoronenes, along with their periodic electrostatic landscape, confines two-dimensional electron gas in Cu(111) into a chiral electronic Kagome-honeycomb lattice with two emergent electronic flat bands. Our findings open up a new route for the high-yield fabrication of elusive nanographenes with zigzag topologies and their superlattices with possible nontrivial electronic properties.

Reactions of heteroleptic [Cu(acac)(AA)(H2O)]+ complexes with carboxylate anions (acac- = acetylacetonate, AA = 2,2’-bipyridine, 1,10-phenanthroline)

The reactions of [Cu(acac)(AA)(H2O)]+ species (AA = 2,2’-bipyridine, 1,10-phenanthroline) with anions derived from 4-methylphenol-2,6-dicarboxylic (H3MeIPA) and isophthalic acids (H2IPA) generate new complexes, which result by substituting the acetylacetonato ligand by carboxylato ones: [Cu(bipy)(HMeIPA)(H2O)]∙0.5H2O∙DMF 1 (DMF = dimethylformamide), 1∞[Cu(bipy)(IPA)(H2O)2]∙H2O∙DMF 2, and 1∞[Cu(phen)(IPA)(H2O)]∙DMF 3. The crystal structures of 1 - 3 have been solved. Compound 1 is a mononuclear complex, while compounds 2 and 3 are one-dimensional coordination polymers with a zigzag topology.

Effect of Substrate on Structural and Electronic Properties of Au-Pd, Au-Pt and Au-Ag Atomic Chains

We report structure and electronic properties of Au-Pd, Au-Pt and Au-Ag bimetallic atomic chains absorbed on NiAl(110) and Cu(110) substrate. It is found that the presence of substrate significantly influences the electronic structure of the chains. Atoms of single chains of Au-Pd, Au-Pt and Au-Ag bind more strongly with Ni atoms of NiAl substrate, as compared with Cu atoms in Cu(110). The interaction between chain atoms is found stronger than the chain-substrate atoms, when chains are placed on Cu substrate, while it is other way round in case of chains on NiAl substrate. Effect of change in positions of atoms in bimetallic chains in presence of substrate is studied by placing double chains of Au-Pd, Au-Pt and Au-Ag on Cu (110) substrate in three different configurations. It is found that Au-Pd and Au-Pt bimetallic chains stabilize in double zigzag topology, when placed on Cu (110) substrate. While Au-Ag chains exhibit ladder topology on Cu(110) substrate. Ferromagnetism that is observed in ground state of free standing chains of Au-Pd and Au-Pt is not found when chains are absorbed on NiAl(110) and Cu(110) substrate. It is likely that the interaction between chain and substrate atoms results to zero magnetic moment.

Crystal structures of two dis-symmetric di-Schiff base compounds: 2-({(E)-2-[(E)-2,6-di-chloro-benzyl-idene]hydrazin-1-yl-idene}meth-yl)-6-meth-oxy-phenol and 4-bromo-2-({(E)-2-[(E)-2,6-di-chloro-benzyl-idene]hydrazin-1-yl-idene}meth-yl)phenol.

Each of the title dis-symmetric di-Schiff base compounds, C15H12Cl2N2O2 (I) and C14H9BrCl2N2O (II), features a central azo-N-N bond connecting two imine groups, each with an E-configuration. One imine bond in each mol-ecule connects to a 2,6-di-chloro-benzene substituent while the other links a 2-hydroxyl-3-meth-oxy-substituted benzene ring in (I) or a 2-hydroxyl-4-bromo benzene ring in (II). Each mol-ecule features an intra-molecular hydroxyl-O-H⋯N(imine) hydrogen bond. The C-N-N-C torsion angles of -151.0 (3)° for (I) and 177.8 (6)° (II) indicates a significant twist in the former. The common feature of the mol-ecular packing is the formation of supra-molecular chains. In (I), the linear chains are aligned along the a-axis direction and the mol-ecules are linked by meth-oxy-C-H⋯O(meth-oxy) and chloro-benzene-C-Cl⋯π(chlorobenzene) inter-actions. The chain in (II) is also aligned along the a axis but, has a zigzag topology and is sustained by Br⋯O [3.132 (4) Å] secondary bonding inter-actions. In each crystal, the chains pack without directional inter-actions between them. The non-covalent inter-actions are delineated in the study of the calculated Hirshfeld surfaces. Dispersion forces make the most significant contributions to the identified inter-molecular inter-actions in each of (I) and (II).

On-Surface Synthesis of Armchair-Edged Graphene Nanoribbons with Zigzag Topology

Graphene nanoribbons (GNRs) are of enormous research interest as a promising active component in electronic devices, for example, field-effect transistors (FET). The recently developed “bottom-up” ...

Coordination polymers and supramolecular solid-state architectures constructed from an organometallic tecton, bis(4-pyridyl)mercury

Four new 1-D coordination polymers have been assembled using bis(4-pyridyl)mercury (py2Hg) as spacer: 1∞[Mn(hfac)2(py2Hg)] 1, 1∞[Zn(CH3COO)2(py2Hg)]∙2H2O 2; 1∞[Ni(dipdtp)2(py2Hg)] 3 (dipdtp = O,O′-diisopropyldithiophosphato), 1∞[Zn(H2O)4(py2Hg)]∙(18C6)(ClO4)24 (18C6 = crown ether 1,4,7,10,13,16-hexaoxacyclooctadecane). The crystal structures of 1, 3, and 4 consist of linear chains, while 2 shows a zigzag topology. The zigzag chains in 2 are assembled into supramolecular layers through weak Hg⋯O interactions, and are further linked into a 3-D framework by tetrameric water clusters. The structure of 3 is expanded into 2-D layers through weak Hg⋯S interactions. In crystal 4, the 18C6 molecules act as second coordination sphere ligands. The supramolecular 3-D network is sustained by hydrogen bonds and Hg⋯O interactions. The system [Cu2(valpa)2]∙(py2Hg) 5 was obtained from a co-crystallization process of py2Hg and the binuclear complex [Cu2(valpa)2] (H2valpa is the Schiff base resulted from the condensation reaction between o-vanillin and propanolamine). The py2Hg molecules in 5 interact each other through N⋯Hg bonds generating layers with square meshes. The organometallic tecton, through the mercury atom, is involved in various weak interactions (Hg⋯O, Hg⋯N, Hg⋯S), which play an important role in sustaining the solid state architectures.

Validation of a Modeling Tool for In-Plane Longitudinal Resonators with Zigzag Topology

Metastructures are viewed as a promising means for suppressing elastic waves and unwanted vibrations. Metastructures comprise of elementary cells with embedded resonators, which act as vibration absorbers. Design and frequency tuning of individual resonators inside the metastructure allows to achieve effective suppression of vibrations over a relatively wide frequency bandwidth, which makes metastructures superior compared to conventional passive vibration absorbers. This paper describes numerical and experimental validation of a modeling tool for design of planar resonators with elastic elements arranged in a zigzag configuration for suppression of longitudinal vibrations. Zigzag topology is advantageous due to its ability to provide higher compliance within a limited space, so as to achieve low resonant frequencies. Natural frequencies predicted by the proposed model agree well with predictions provided by detailed finite element models and experimental measurements.

On topology-tuned thermoelectric properties of noble metal atomic wires

We have carried out a systematic first principles study of thermal and thermoelectric transport properties of different noble metal (viz. Ag, Cu, Au, and Pt) atomic wires modelled in different topologies by using the Landauer-Büttiker approach in the linear response regime. Both electronic and phononic contributions are considered, with the respective transmission functions determined using the non-equilibrium Green's function approach, based upon the density functional theory and the general utility lattice program, respectively. To explore the role of topology, we have considered the linear, ladder, zigzag (ZZ), and double zigzag (DZZ) topologies for each of the four wires. Numerical results are presented for the electronic κel and phononic κph thermal conductance, thermopower S, and total figure of merit ZT. In addition, the validity of the Wiedemann-Franz law in these atomic wires has been studied. Quite generally, we find a significant dependence of these properties on the wire topology. Under ambient conditions, the valence electrons are found to be the dominant carriers of heat energy in all the wires, except for the Ag, Cu, and Au wires in the DZZ topology due to their semi-metallic nature. In relative terms, the phononic contribution is minimum (∼ 4%) for the Pt wire in linear topology, while maximum (∼ 15%) for the Cu wire in ZZ topology. However, the phonon contribution increases steadily with decreasing temperature to become as large as about 30% at T = 100 K (for Cu wire in ZZ topology). In overall, the Pt wire is found to have the maximum total thermal conductance in all topologies. S and ZT, apart from depending on topology and type of metal wire, exhibit an oscillatory behaviour as a function of chemical potential μ of electrodes. S has been found to change even its sign at characteristic μ, with a maximum value of ∼±1.5 mV/K for the Au wire in DZZ topology at μ = ∓0.15 eV. Also, ZT is found to be maximum (∼ 3) for this wire, with the presence of two pronounced peaks at μ ∼±0.6 eV, apparently located at somewhat higher μ as compared to S. An analysis of our results reveals that the change in thermoelectric properties with topology stems primarily from a change in electronic band structure and phonon spectra.

Alloying-induced spin Seebeck effect and spin figure of merit in Pt-based bimetallic atomic wires of noble metals.

We have investigated using first principles the occurrence and tunability of the spin Seebeck effect in Pt-based bimetallic wires of noble metals (viz. XPt, X = Cu, Ag, and Au) modelled in linear, ladder, and double zigzag (DZZ) topologies. The spin figure of merit ZsT and its charge counterpart ZcT are calculated by considering both electronic and phononic contributions to the thermal conductance. For this endeavour, we have employed the Landauer-Büttiker approach, with the requisite electron τel(E) and phonon τph(E) transmission functions obtained using the non-equilibrium Green's function approach, based on density functional theory and the general utility lattice program, respectively. We find that alloying and/or topological tailoring bring in quantitative as well as qualitative changes in the transport properties. Unlike the pristine wires, τel(E) now depends (except for the CuPt wire in the ladder topology) markedly on spin, thus resulting in an unequal current in the two spin channels and hence a non-zero spin Seebeck coefficient Ss. Remarkably, the AgPt wire in the linear topology and all wires in the DZZ1 and DZZ3 configurations of the DZZ topology exhibit half-metallic conduction, with a sizable gap in the density of ↑-spin states at the Fermi level. Alloying also introduces energy gap(s) in the phonon density of states. Consequently, we find a significant reduction in the electronic and phononic thermal conductance. Interestingly, Ss is of the same order as its charge counterpart Sc, and both can be tuned via the topology and chemical potential μ of the electrodes. This together with the reduced thermal conductance results in a significantly high room-temperature ZcT (∼33) and ZsT (∼25) at μ ∼ 0.24 eV in the AgPt wire in the DZZ3 topology, with about a ten-fold increase in ZcT as compared to the pristine wires. Furthermore, there exists a characteristic μ in some bimetallic wires for which Sc approaches zero, but Ss remains quite appreciable. This result arises due to the emergence of bipolar thermal conduction, which under criticality makes S↑ + S↓ = 0. Importantly, such a situation may be exploited to generate a pure thermal spin voltage. Our results can be explicated on the basis of changes in the electronic band structure and phononic spectra due to alloying and topological effects.

Anion-π Architectures of HAT(CN)6 and 5d Polycyanidometalates: [W(CN)8]3–, [Re(CN)7]3–, and [Pt(CN)6]2–

Homoleptic polycyanido-complexes of 5d metal ions with high coordination numbers (C.N.), 8 for [W(CN)8]3–, 7 for [Re(CN)7]3–, and 6 for [Pt(CN)6]2–, are found to form supramolecular anion-π chains with the multisite anion receptor HAT(CN)6 (hexaazatriphenylenehexacarbonitrile). The chains adopt a zigzag topology in the case of (XPh4)3[W(CN)8]·HAT(CN)6 (X = P: 1, X = As: 2) and (PPh4)3[Re(CN)7]·HAT(CN)6 (3), and a linear arrangement in the case of (PPh4)2[Pt(CN)6]·HAT(CN)6·0.5CH3CN·2Et2O (4). The anion-π interactions consist of 3-fold {M–C≡N–···δ+centroidpyrazine,ring}3 or single {M–C≡N–···δ+centroidpyrazine,C–C bond} intermolecular contacts with separation distances in the range of 2.79–3.20 A. An M-(CN)− → HAT(CN)6 charge transfer (CT) along these anion-π contacts is evidenced in the solid state by the appearance of new absorptions in the visible range of UV–vis electronic absorption spectra, as compared to the starting materials, and by dispersion-corrected density functional theory studies. The CT anio...

Oxygen-Doped Zig-Zag Molecular Ribbons.

The synthesis of a zig-zag oxygen-doped molecular rhombic ribbon has been achieved. This includes oxidative C-C and C-O bond formations that allowed the stepwise elongation and planarization of an oxa-congener of 2,7-periacenoacene. X-ray diffraction analysis corroborated the flat structure and the zig-zag topology of the O-doped edges. Photophysical and electrochemical investigations showed that the extension of the peri-xanthenoxanthene (PXX) into the molecular ribbon induces a noticeable shrinking of the molecular band gap devised by a rising of the HOMO energy level, a desirable property for p-type organic semiconductors.

A 60 GHz Horizontally Polarized Magnetoelectric Dipole Antenna Array With 2-D Multibeam Endfire Radiation

A novel substrate integrated waveguide (SIW) fed horizontally polarized endfire magnetoelectric (ME) dipole antenna composed of an open-ended SIW with broad walls vertical to substrates and a pair of electric dipoles realized by four metallic patches is proposed. Simple configuration and excellent performance including an impedance bandwidth of 46.5%, stable gain of around 6 dBi, and symmetrical cardioid radiation patterns with low backward radiation and low cross polarizations are achieved. An SIW 90° twist integrated in three-layered substrate is implemented in order to connect the ME-dipole antenna conveniently to the SIW beam-forming network with broad walls parallel to substrates. A $4 \times 4$ SIW Butler matrix with a three-layered zigzag topology is then designed, which enables a size reduction of 45% for the matrix compared with conventional single-layered configuration but not affecting its operating characteristics. By employing a $2 \times 4$ ME-dipole array with 90° twists, two-folded Butler matrices and four SIW 3 dB E-plane couplers, a multibeam endfire array that can radiate eight beams scanning in two dimensions is designed at the 60 GHz band. The fabricated prototype verifies that a wide impedance bandwidth of 22.1%, gain varying from 10 to 13 dBi and stable radiation beams can be obtained. Due to good performance and the compact structure with low fabrication costs, the proposed design would be attractive for future millimeter-wave wireless applications including 5G communications and the WiGig system.

Decrypting Strong and Weak Single-Walled Carbon Nanotubes Interactions with Mitochondrial Voltage-Dependent Anion Channels Using Molecular Docking and Perturbation Theory

The current molecular docking study provided the Free Energy of Binding (FEB) for the interaction (nanotoxicity) between VDAC mitochondrial channels of three species (VDAC1-Mus musculus, VDAC1-Homo sapiens, VDAC2-Danio rerio) with SWCNT-H, SWCNT-OH, SWCNT-COOH carbon nanotubes. The general results showed that the FEB values were statistically more negative (p < 0.05) in the following order: (SWCNT-VDAC2-Danio rerio) > (SWCNT-VDAC1-Mus musculus) > (SWCNT-VDAC1-Homo sapiens) > (ATP-VDAC). More negative FEB values for SWCNT-COOH and OH were found in VDAC2-Danio rerio when compared with VDAC1-Mus musculus and VDAC1-Homo sapiens (p < 0.05). In addition, a significant correlation (0.66 > r2 > 0.97) was observed between n-Hamada index and VDAC nanotoxicity (or FEB) for the zigzag topologies of SWCNT-COOH and SWCNT-OH. Predictive Nanoparticles-Quantitative-Structure Binding-Relationship models (nano-QSBR) for strong and weak SWCNT-VDAC docking interactions were performed using Perturbation Theory, regression and classification models. Thus, 405 SWCNT-VDAC interactions were predicted using a nano-PT-QSBR classifications model with high accuracy, specificity, and sensitivity (73–98%) in training and validation series, and a maximum AUROC value of 0.978. In addition, the best regression model was obtained with Random Forest (R2 of 0.833, RMSE of 0.0844), suggesting an excellent potential to predict SWCNT-VDAC channel nanotoxicity. All study data are available at https://doi.org/10.6084/m9.figshare.4802320.v2.

A one-dimensional coordination polymer, catena-poly[[[[N-ethyl-N-(pyridin-4-ylmeth-yl)di-thio-carbamato-κ2S,S']zinc(II)]-μ2-N-ethyl-N-(pyridin-4-ylmeth-yl)di-thio-carbamato-κ3S,S':N] 4-methyl-pyridine hemisolvate

The title compound, {[Zn(C9H11N2S2)2]·0.5C6H7N} n , comprises two independent, but chemically similar, Zn[S2CN(Et)CH2py]2 residues and a 4-methyl-pyridine solvent mol-ecule in the asymmetric unit. The Zn-containing units are connected into a one-dimensional coordination polymer (zigzag topology) propagating in the [010] direction, with one di-thio-carbamate ligand bridging in a μ2-κ3 mode, employing one pyridyl N and both di-thio-carbamate S atoms, while the other is κ2-chelating. In each case, the resultant ZnNS4 coordination geometry approximates a square pyramid, with the pyridyl N atom in the apical position. In the crystal, the chains are linked into a three-dimensional architecture by methyl- and pyridyl-C-H⋯S, methyl-ene-C-H⋯N(pyrid-yl) and pyridyl-C-H⋯π(ZnS2C) inter-actions. The connection between the chain and the 4-methyl-pyridine solvent mol-ecule is of the type pyridyl-C-H⋯N(4-methyl-pyridine).