Bond Lengths Research Articles

Identification of heterozygous mutations of ABCC8 gene responsible for maturity-onset diabetes of the young with exome sequencing

Abstract Background Although the MODY12 subtype, caused by ABCC8 mutations, is rare, it is highly sensitive to sulfonylureas. The identification of ABCC8 mutations in patients clinically diagnosed with MODY has the ability to contribute to the precise management of diabetes. Methods Genetic analysis of two families with MODY were conducted using whole-exome sequencing (WES) and Sanger sequencing. The spatial structures of the mutant proteins were constructed using MODELLER and PyMOL software to provide further evidence of pathogenicity. Results The heterozygous missense mutations V357I and R1393H in ABCC8 were found in probands of two unrelated MODY pedigrees, which co-segregated with the hyperglycemic phenotypes in these two pedigrees. Detection of the V357I mutation enabled the proband of family A to successfully transfer from insulin to sulfonylurea (SU). After 3 months of follow-up for the SU trial, the HbA1c level of proband A improved from 12.4% at the initial diagnosis to 7.20%. Proband B was treated with insulin because of pregnancy and poor islet function. In silico analysis indicated that the R1393H mutation resulted in a longer hydrogen bond distance to L1389 and cleavage of carbon-hydrogen bonds to V1395, A1390, and L1389. Conclusions We have described two pathogenic missense mutations in ABCC8 in Chinese families with MODY. Our findings support the heterogeneity in the clinical features of MODY12 caused by ABCC8 mutations.

Unexpected XPS Binding Energy Observations Further Highlighted by DFT Calculations of Ruthenocene-Containing [IrIII(ppy)2(RCOCHCORc)] Complexes: Cytotoxicity and Crystal Structure of [Ir(ppy)2(FcCOCHCORc)

The series of iridium(III) complexes, [Ir(ppy)2(RCOCHCOR′)], with R = CH3 and R′ = CH3 (1), Rc (2), and Fc (3), as well as R = Rc and R′ = Rc (4) or Fc (5), and R = R′ = Fc (6), ppy = 2-phenylpyridinyl, Fc = FeII(η5–C5H4)(η5–C5H5), and Rc = RuII(η5–C5H4)(η5–C5H5), has been investigated by single-crystal X-ray crystallography and X-ray photoelectron spectroscopy (XPS) supplemented by DFT calculations. Here, in the range of 3.74 ≤ ΣχR ≤ 4.68, for Ir 4f, Ru 3d and 3p and N 1s orbitals, binding energies unexpectedly decreased with increasing ΣχR (ΣχR = the sum of Gordy group electronegativities of the R groups on β-diketonato ligands = a measure of electron density on atoms), while in Fe 2p orbitals, XPS binding energy, as expected, increased with increasing ΣχR. Which trend direction prevails is a function of main quantum level, n = 1, 2, 3…, sub-quantum level (s, p, d, and f), initial state energies, and final state relaxation energies, and it may differ from compound series to compound series. Relations between DFT-calculated orbital energies and ΣχR followed opposite trend directions than binding energy/ΣχR trends. X-ray-induced decomposition of compounds was observed. The results confirmed good communication between molecular fragments. Lower binding energies of both the Ir 4f7/2 and N 1s photoelectron lines are associated with shorter Ir-N bond lengths. Cytotoxic tests showed that 1 (IC50 = 25.1 μM) and 3 (IC50 = 37.8 μM) are less cytotoxic against HeLa cells than cisplatin (IC50 = 1.1 μM), but more cytotoxic than the free β-diketone FcCOCH2COCH3 (IC50 = 66.6 μM).

An Acceptor-Substituted N-Heterocyclic ortho-Quinodimethane: Pushing the Boundaries of Polarization in Donor-Acceptor-Substituted Polyenes.

We report the synthesis, isolation, and characterization of a stable donor-acceptor substituted ortho-quinodimethane (oQDM). This system with an imidazolidine scaffold as the donor can also be referred to as acceptor-substituted ortho-N-heterocyclic quinodimethane (oNHQ). We have examined the extent of polarization of the conjugated π-system using single-crystal X-ray diffraction, NMR and UV/vis spectroscopy, cyclic voltammetry, and DFT computations. The bond lengths in the phenyl linker do not exhibit the alternation typical of oQDMs. In addition, the 13C and 15N NMR shifts suggest significant charge separation, an interpretation supported by the diatropic ring current determined by NICSZZ(r) computations, which is characteristic of aromatic compounds. DFT calculations show that polarization is an electronic effect that is amplified by steric influences. More strikingly, the oxidation and reduction potentials of the push-pull substituted oQDM are virtually identical to those of authenticated anionic and cationic derivatives. The results therefore indicate that an aromatic zwitterionic structure represents the electronic structure more accurately than a neutral quinoidal Lewis structure, which indicates that the acceptor-substituted oNHQ is a rare example of an organic zwitterion in which the centers of charge are in conjugation. The ambiphilic reactivity of the acceptor-substituted oNHQ, which is evidenced by the dehydrogenation of ammonia borane and the addition of phenylacetylene via heterolytic C-H bond cleavage, further supports its notation as an organic zwitterion and is reminiscent of frustrated Lewis pairs (FLPs). Thus, the acceptor-substituted oNHQ can be considered to be an intramolecular carbogenic FLP in terms of its reactivity.

Relativistic Prolapse-Free Gaussian Basis Sets of Double- and Triple-ζ Quality for s- and p-Block Elements: (aug-)RPF-2Z and (aug-)RPF-3Z.

This study presents two new relativistic Gaussian basis sets without variational prolapse of double- and triple-ζ quality, RPF-2Z and RPF-3Z, along with augmented versions including additional diffuse functions, aug-RPF-2Z and aug-RPF-3Z, which are available for all s and p block elements from Hydrogen to Oganesson. The exponents of the Correlation/Polarization (C/P) functions are obtained from a polynomial version of the generator coordinate Dirac-Fock method (p-GCDF). The choice of C/P functions was guided by multireference configuration interaction calculations with single and double excitations (MR-CISD) based on a valence active space. Finally, calculations of fundamental properties done for atomic and molecular systems (bond lengths, vibrational frequencies, dipole moments, and electron affinities) ensure the expected quality of these new basis sets, which may also exhibit some computational efficiency advantages. Additionally, the prolapse-free feature of these sets must provide a reliable description of properties more dependent on core electron distributions, as well.

Modulating RuO2 Electrocatalysis via Introducing Lanthanides for Enhanced Acidic Oxygen Evolution

AbstractThe low activity of ruthenium dioxide (RuO2) and the rapid dissolution of the ruthenium (Ru) site during acid oxygen evolution reaction (OER) at high current density restricts its application in proton exchange membrane (PEM) electrolyzers. In this work, a series of rare‐earth (RE) elements doped RuO2 nanorods is developed as high‐performance OER electrocatalysts. X‐ray absorption spectroscopy suggests that RE doping regulates the local coordination environment around Ru sites, lowers the valance of Ru, and shortens the Ru─O─Ru(M) bond length, which enhances structural stability. Among the RE‐RuO2 samples, Sm‐RuO2 exhibits remarkable performance with a low overpotential of 283 mV to reach 100 mA cm−2 and maintained stability for over 140 h at 10 mA cm−2. Moreover, the PEM electrolyzer using Sm‐RuO2 as the anode can be stably operated at 500 mA cm−2 for 15 h. Electrochemical analysis, X‐ray photoelectron spectroscopy, and in situ Raman spectroscopy show that Sm doping lowers the d‐band center, reduces the adsorption energy of O intermediates to enhance the OER activity, and restrains excessive oxidation of Ru sites while stabilizing lattice oxygen during the OER process, thereby enhancing OER stability. This work offers valuable insights into improving the stability of metal oxide catalysts in acidic electrolytes.

Experimental Determination of the Relationship between S=O Bond Length and Its Stretching Frequency of DMSO Molecule

Abstract Time-of-flight (TOF) neutron diffraction, X-ray diffraction and attenuated total reflection infrared (ATR-IR) spectroscopic measurements have been carried out for pure deuterated dimethylsulfoxide (DMSO-d6), concentrated 20 mol% lithium bis(trifluorosulfonyl)amide (LiTFSA) –DMSO-d6 , 14 mol% LiCl-DMSO and 3 mol% NiCl2-DMSO solutions in order to obtain the relationship between intramolecular S=O bond length (rSO) and its stretching vibrational frequency (νSO) in the liquid state. The S=O bond length of DMSO molecule has been determined from the least squares fitting analysis of neutron and X-ray total interference terms observed in the high-Q region. The νSO-rSO plot involving the present results and experimental data reported for gaseous and crystalline DMSO as well as DMSO complexes with metal ions, has indicated that the νSO-rSO relationship is well approximated by a linear function. The value dνSO/drSO = -3600 ± 400 cm-1Å-1 was obtained from slope of the fitted function. It has been revealed that the S=O bond length of DMSO molecule sensitively reflects intermolecular interactions receiving from its environment.

Probing the Electronic Manifold of MgCl with Millimeter-Wave Spectroscopy and Theory: (3)2Σ+ and (4)2Σ+ States.

The millimeter/submillimeter spectrum of magnesium chloride (MgCl) has been observed in two new electronic excited states, (3)2Σ+ and (4)2Σ+, using direct absorption methods. The molecule was synthesized in a mixture of Cl2, argon, and magnesium vapor. For the (3)2Σ+ state, multiple rotational transitions were measured in the v = 0 level for all six isotopologues (24Mg35Cl, 24Mg37Cl, 25Mg35Cl, 25Mg37Cl, 26Mg35Cl, and 26Mg37Cl), as well as up to v = 13 for 24Mg35Cl. For the (4)2Σ+ state, less intense spectra were recorded for 24Mg35Cl (v = 0-2). Equilibrium rotational parameters were determined for both states for 24Mg35Cl, as well as rotational constants and 25Mg hyperfine parameters for the other isotopologues. A perturbation was observed between rotational levels of the two states due to an avoided crossing. Computations were also carried out at the CASPT2 and MRCISD+Q levels, and the resulting bond lengths for (3)2Σ+ and (4)2Σ+ states agree well with the experimental values of re = 2.536 and 2.361 Å. The computations show that the (3)2Σ+ state has a double-well potential; however, the state behaves as a single well with unperturbed vibrational levels up to v = 13 due to nonadiabatic interactions with the (4)2Σ+ state.

Optimization across-the-Board: Centro-Arylated Push-Pull Tetraene Chromophores and Guest-Host Polymers for Electro-Optics.

The research and development of push-pull tetraene chromophores (PPT-phores) have contributed greatly to the field of organic electro-optic (EO) materials and devices since the inauguration of CLD-1 in 2001. This study is thus a systematic contribution to synthesize and characterize a series of centro-arylated PPT-phores based on strong electron-donating tetrahydroquinolinyl groups and variable strong electron-accepting tricyanofuran derivatives. In particular, we report the crystallographic data to show various packing modes of these PPT-phores with detailed information about bond length alternation and intermolecular interactions, the optical absorption edges of guest-host polymers by the Tauc model, and the anisotropy and dispersion of Pockels tensors for the poled polymers by attenuated total reflection spectroscopy. Such analyses have not been addressed to any significant extent previously and are fundamentally important to the future development of PPT-phore-based EO materials and devices. The poled films of several centro-arylated PPT-phores in polycarbonates exhibited large EO activities, excellent thermal stability, and tunable optical transparency at the telecom O- and C-band. The study demonstrates the effectiveness of π-bridge centro-arylation enabled by molecular shape modification and rigidity enhancement, over the relatively flexible and labile thioether or alkoxy groups, in rational design of hyperpolarizable PPT-phores for high-performance EO polymers.

Uranyl–Nickel(II) Cation–Cation Interaction in a Triperiodic Framework with cis‐1,2‐Cyclohexanedicarboxylate and Isonicotinate Ligands

Uranyl and nickel(II) nitrates have been reacted with cis‐1,2‐cyclohexanedicarboxylic (H2chdc) and isonicotinic (Hint) acids under solvo‐hydrothermal conditions, giving the heterometallic, mixed‐ligand complex [(UO2)2Ni(chdc)2(int)2]⋅CH3CN (1). The uranyl cation is bound to carboxylate groups of both ligands while NiII is attached to two carboxylate and two nitrogen donors, with two strong additional interactions with uranyl oxo groups giving a nearly regular octahedral environment. The short Ni–O(oxo) bond length of 2.114(3) Å amounts to 67% of the sum of van der Waals radii. The trimetallic (UO2)2Ni6+ clusters thus formed are assembled by chdc2– ligands into linear chains which are further bridged by int– links to give a triperiodic framework with the dia topology, in which small channels encompass two rows of acetonitrile solvent molecules. Complex 1 does not display uranyl luminescence under excitation in the solid state.

Assessing many-body methods on the potential energy surface of the (H2)2 hydrogen dimer.

The anisotropic potential energy surface of the (H2)2 dimer represents a challenging problem for many-body methods. Here, we determine the potential energy curves of five different dimer configurations (T, Z, X, H, and L) using the lattice regularized diffusion Monte Carlo method and a number of approximate functionals within density functional theory (DFT), including advanced orbital-dependent functionals based on the random phase approximation (RPA). We assess their performance in describing the potential wells, bond distances, and relative energies. The repulsive potential wall is studied by looking at the relative stability of the different dimer configurations as a function of an applied force acting along the intermolecular axis. It is shown that most functionals within DFT break down at finite compression, even those that give an accurate description around the potential well minima. Only by including exchange within RPA, a qualitatively correct description along the entire potential energy curve is obtained. Finally, we discuss these results in the context of solid molecular hydrogen at finite pressures.

Comprehensive Theoretical Insights on Spectroscopic Characterization, Solvent Effect (Polar and Nonpolar) in Electronic behavior, Topological Insights, and Molecular Docking Prediction of Taurolidine

In recent decades, sulfur-containing compounds have played a significant role in biological applications because of their unique biological and chemical characteristics. Taurolidine, a sulfur-containing derivative of the amino acid taurine, has been characterized theoretically utilizing Density Functional Theory (DFT) at the B3LYP approach along with a 6-311++G(d,p) basis set. The impact of solvents on electronic characteristics, Molecular electrostatic potential (MEP), and Fourier Molecular Orbital (FMO) in polar (water and ethanol) and nonpolar (toluene and chloroform) has been analyzed. The bond distances of S1-C16 and S1-C17 have been simulated at 1.817 Å and observed at 1.743 and 1.739 Å, respectively. These distances are increased compared to other bond distances due to the influence of sulfur atoms. The distinctive simulated vibrational wavenumbers of taurolidine revealed peaks for SO2, CH2, CN, and NH groups. The intramolecular interactions responsible for stabilizing the molecular structure of taurolidine have been addressed using NBO analysis shows significant stabilization energy from electron-donating lone pair oxygen O6 to antibonding S2-N10 with the stabilizing energy of 19.88 KJ/mol by the transition of LP(3)- σ*. The bonding characteristics and reactive sites (electron-rich and electron-poor) have been confirmed with Mulliken and MEP analysis. The carbons (C17 and C16) emphasize the increased negative potential due to the sulfonyl (SO2) group in the ortho position. The topological insights, ELF and LOL, were spotted using Multiwfn software, highlighting the localized and delocalized electron regions within the crystal structure. In addition, molecular docking was performed to predict the antagonist activity of taurolidine against β-catenin protein, yielding a binding energy of -6.86 KJ/mol, which confirms its antiproliferative property.

High-Pressure Behaviors of Hydrogen Bonds in Fluorine-Doped Brucite.

Brucite, Mg(OH)2 (P3̅m1, Z = 1), is a prototype material for studying hydrogen bonds in solid hydroxides. In this study, substitutional effects of fluorine (F) on the hydrogen-bonding geometries of hydrogenated and deuterated brucite were investigated under ambient conditions and at high pressure using combined experimental methods of neutron powder diffraction, Raman spectroscopy, and infrared (IR) spectroscopy. Under ambient conditions, neutron powder diffraction results showed that F substitution decreased the donor-acceptor distance and increased the hydroxyl covalent bond lengths of both hydrogenated and deuterated brucite, strengthening the hydrogen bond. Red shifts of the hydroxyl stretching modes also indicated an elongation of d(O-H) and d(O-D). High-pressure neutron diffraction experiments were performed on Mg(OH)1.81F0.19 and Mg(OD)1.74F0.26 up to 7.04 and 10.02 GPa, respectively. For both samples, changes in the hydrogen-bonding geometries did not indicate hydrogen-bond strengthening under high pressure. Compared with Mg(OD)2, the doping of F suppressed the increase of the hydroxyl covalent bond length, the hydrogen-bond angle, and the cone angle, inhibiting pressure-induced hydrogen-bond strengthening. High-pressure Raman and IR absorption spectroscopic measurements on Mg(OD)2 and Mg(OD)1.79F0.21 up to 9.7 and 13.7 GPa confirmed that F substitution restrains pressure-induced hydroxyl elongation.

Solution of Schrödinger Equation for Simple Diatomic Molecules Using One‐Parameter 1s Slater‐Type Orbitals Wave Function

ABSTRACTThe Schrödinger equation for simple homonuclear and heteronuclear diatomic molecules is analytically solved using one‐parameter Slater‐type orbitals (STOs) to approximate the electronic wave function within a molecular orbital (MO)‐like approach. The resulting total energies, equilibrium bond lengths, potential curves, and electron densities are presented in detail. Calculations using a selected orbital exponent accurately reproduce results from standard methods. Furthermore, the optimization of the orbital exponent allows for a more accurate representation of the electronic wave function, leading to the improved results of the total energy and the equilibrium bond length, as well as minimal computational cost. Seen in the heteronuclear diatomic molecule, the use of the one‐parameter STOs allows the transformation of the heteronuclear problem into the homonuclear one, revealing the electron repulsion effect on the orbital exponent parameter.

Tetracyanoethylene Na+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {Na}^+$$\\end{document}/K+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {K}^+$$\\end{document} radical anion coordination sites unveiled via electronic and vibrational fingerprints

Tetracyanoethylene (TCNE) is a very effective electron acceptor and can form stable complexes with various chemical species and is known for its interesting electronic and optical properties. The formation of the monoanion gives TCNE unique electronic and chemical properties, making it a material of interest for several technological applications including solar cells, organic battery electrodes, sodium/potassium-ion batteries and information storage devices. The chemico-physical characterization of Na+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {Na}^+$$\\end{document} and K+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {K}^+$$\\end{document} coordination of TCNE in solution is not available so far, although it would be valuable for understanding the molecular mechanisms of charging and discharging processes in innovative battery devices. The present theoretical-computational study characterizes the vibrational and electronic properties of ion-coordinated TCNE in solution. We analyzed the ground electronic state through equilibrium structures, focusing on structural features, stability, optical properties and Raman vibrational modes. The Na+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {Na}^+$$\\end{document} and K+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {K}^+$$\\end{document} cations, coordinated at two distinct sites, significantly alter the geometry, and modulate electronic and vibrational properties. Using ab initio molecular dynamics simulations, we computed vibrational spectra, finding that TCNE complexes serve as effective probes for detecting environmental variations, with key vibrational modes on CC and CN moieties being sensitive to cation interactions. Additionally, a correlation between C=C bond distances and vibrational frequencies was observed. In conclusion, this study provides further insight into the role of TCNE in optoelectronic applications and nonaqueous battery systems.

Mechanism insights and experimental feasibility of using boron nitride nanocones for rapid adsorption and degradation of SF6 decomposition compounds

Gas-insulated switchgear (GIS) employs sulfur hexafluoride (SF6) as an insulating medium to shield electrical gadget. However, SF6 can decompose under sure situations, generating dangerous sulfur-based totally compounds which include SO2, SOF2, and SO2F2. These byproducts pose enormous dangers to both protection and environmental integrity. Efficiently adsorbing and disposing of those compounds is critical for ensuring operational reliability and reducing environmental dangers. This study investigates the adsorption and degradation mechanisms of SF₆ decomposition compounds (SO₂, SOF₂, and SO₂F₂) on boron nitride nanocones (BNNCs) using density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Our comprehensive analysis covers five distinct systems, exploring individual and combined adsorption scenarios. The findings reveal that the apex of BNNCs plays a crucial role in the adsorption process, showing high efficiency in adsorbing SO₂ (adsorption energy − 1.22 eV) and facilitating the catalytic breakdown of SOF₂ (adsorption energy − 1.57 eV). The positively charged potential at the nanocone’s apex significantly influences the dissociation and subsequent adsorption of fluorine atoms, with an energy barrier for F dissociation at the apex (1.8 kcal/mol) much lower than at the sidewall (5.3 kcal/mol). In gas mixtures, SO₂ preferentially binds to the apex region of BNNCs, with a bond length of approximately 1.38 Å. BNNCs demonstrate superior adsorption capabilities for SO₂ and SOF₂ compared to other boron nitride nanostructures, with adsorption energies up to 89% higher. The electron transfer analysis reveals that BNNC complexes act as potent electron donors, particularly in the case of BNNC@3SO₂F₂. Additionally, BNNCs show significant potential as sensors for detecting SO₂F₂, with a rapid recovery time of 4.67 ps and a notable decrease in the Fermi level energy to -4.97 eV upon adsorption. The study also provides insights into the angular distribution and charge density difference profiles, offering a detailed understanding of the adsorption mechanisms. These findings have important implications for improving the safety and efficiency of gas-insulated switchgear (GIS) and contribute to the development of more effective environmental protection solutions in electrical power systems.

Hierarchical Multi‐Component Self‐Assembly Involving Alkali and Lanthanide(III) Metal Ions and Water Soluble Sulfonated Calix[4]arene

AbstractSolid state structural studies of three supramolecular coordination complexes establish the formation of hetero‐bimetallic two‐ and three‐dimensional ensembles involving sulfonated calix[4]arene, and sodium ions and low nuclearity lanthanide(III) ions. The interplay of components is altered in response to the addition of different auxiliary molecules during crystallisation which is associated with significant changes in the metal coordination environments and overall molecular packing, as established in comparing the structures of complexes of similar cell dimensions with those available in the literature. The sulfonated calixarene form a common self‐assembly array despite different lanthanides being incorporated, as an isostructural series of complexes. Crystallographic analysis shows a continually decreasing trend in the lanthanide–oxygen bond length as the lanthanide atomic number increases. As smaller molecules are incorporated to the hetero‐bimetallic calixarene system, the self‐assembly and the metal coordination environment are perturbed.

QSLE-v1.0: A New Software Package for the Calculation of Coupled Quantum-Classical Dynamics in Condensed Phases Based on a Stochastic Approach.

Recently, a stochastic version of the quantum-classical Liouville equation has been proposed [Campeggio, J.; Cortivo, R.; Zerbetto, M. J. Chem. Phys. 2023, 158, 244104], to compute the coupled quantum-classical dynamics of molecules in condensed phases. The approach, called quantum-stochastic Liouville equation (QSLE), is based on coupling the time evolution of electronic states to a stochastic description of the relevant (classical) nuclear coordinates. Natural internal coordinates are used, i.e., bond lengths, bond angles, and dihedral angles. The approach is tailored to directly propagate the populations of the electronic states over time, based on a classical Fokker-Planck equation for the nuclear degrees of freedom coupled to a master equation for the jumps among the electronic states. The QSLE is a multiscale approach requiring many ingredients to be assembled in order to carry out the numerical solution. To make the approach accessible, a software package that handles the main (and most cumbersome) details of the numerical workflow has been implemented into the software package QSLE-v1.0, which is introduced in the present paper. Here, it is considered the case of one torsional nuclear coordinate and two nonadiabatic electronic potential energy surfaces. This is a very basic model for interpreting photoisomerization or charge transfer phenomena, but despite its simplicity, it can be applied even in complex systems where the relevant quantum/classical parts affecting the phenomena under study are highly localized. A sand-box model system for describing photoisomerization processes is reported to demonstrate the usage of the software package. QSLE-v1.0 is open source and distributed under the GPLv2.0 license.

Stable Mono‐radical and Triplet Diradicals Based on Allylic Radical‐Embedded All‐benzenoid Polycyclic Hydrocarbons

High‐spin organic radicals are notable for their unique optical, electronic, and magnetic properties, but synthesizing stable high‐spin systems is challenging due to their inherent reactivity. This study presents a novel strategy for designing stable high‐spin polycyclic hydrocarbons (PHs) by incorporating allylic radical into fused aromatic benzenoid rings. To enhance stability, large steric hindrance groups with a synergistic captodative effect were added to the allylic radical centers. This approach was applied to synthesize derivatives of two open‐shell all‐benzenoid PHs: benzo[fg]tetracene (1) and dibenzo[fg,lm]heptacene (2). Both compounds exhibited excellent stability, with diradical 2 showing a half‐life of up to 17.2 days under ambient conditions. Bond length analysis and theoretical calculations suggest that 1 and 2 predominantly feature Clar’s aromatic sextet structures with embedded allylic radicals. Compound 2 was confirmed to have a triplet ground state through DFT calculations and experimental methods, including pulse EPR spectroscopy and SQUID measurements. This work introduces a new design strategy for stable high‐spin hydrocarbons, paving the way for future developments in high‐spin organic materials.

Stable Mono-radical and Triplet Diradicals Based on Allylic Radical-Embedded All-benzenoid Polycyclic Hydrocarbons.

High-spin organic radicals are notable for their unique optical, electronic, and magnetic properties, but synthesizing stable high-spin systems is challenging due to their inherent reactivity. This study presents a novel strategy for designing stable high-spin polycyclic hydrocarbons (PHs) by incorporating allylic radical into fused aromatic benzenoid rings. To enhance stability, large steric hindrance groups with a synergistic captodative effect were added to the allylic radical centers. This approach was applied to synthesize derivatives of two open-shell all-benzenoid PHs: benzo[fg]tetracene (1) and dibenzo[fg,lm]heptacene (2). Both compounds exhibited excellent stability, with diradical 2 showing a half-life of up to 17.2 days under ambient conditions. Bond length analysis and theoretical calculations suggest that 1 and 2 predominantly feature Clar's aromatic sextet structures with embedded allylic radicals. Compound 2 was confirmed to have a triplet ground state through DFT calculations and experimental methods, including pulse EPR spectroscopy and SQUID measurements. This work introduces a new design strategy for stable high-spin hydrocarbons, paving the way for future developments in high-spin organic materials.

Evaluating the antidiabetes and antioxidant activities of halogenated Schiff bases derived from 4-(diethylamino)salicylaldehyde: in vitro antidiabetes, antioxidant and computational investigation

Six Schiff bases with general name 5-(diethylamino)-2-(((halophenyl)imino)methyl)phenol (where halo = 4-fluoro (H1), 2-fluoro (H2), 2-bromo (H3), 4-bromo (H4), 4-chloro (H5) and 3-chloro-4-fluoro (H6)) were prepared by the condensation reaction between 4-(diethylamino)salicylaldehyde and suitable halogenated aromatic amines. The six halogenated Schiff bases were elucidated using different spectroscopic techniques and the structure of H3 and H6 were confirmed using single-crystal X-ray crystallography. The bond lengths of C7–N1, C7–C8 and C8–C9 obtained from structural analysis for both compounds depicted their enol-tautomeric characteristic form. The Hirshfeld analysis revealed that H‧‧‧H intermolecular contacts contributed most towards the Hirshfeld surfaces of both H3 (47.6%) and H6 (39.9%). Quantum chemical calculation studies showed that H1 and H2 have the highest and lowest energy band gap (∆E = 3.80 eV for H1 and ∆E = 3.73 eV for H2), depicting H2 and H1 as the most and least chemically reactive respectively among all the compounds. α-Amylase and α-glucosidase assay were used to evaluate the antidiabetes prowess of the synthesized compounds. All the compounds exhibited lower IC50 values than acarbose (reference drug) in α-amylase assay experiments and H5 with lowest IC50 value of 63.54 μM could be suggested to have the highest α-amylase inhibitory potential among the test samples. For α-glucosidase assay, H1–H6 displayed good antidiabetic potential. However, none of the compounds outshined acarbose with H6 having highest α-glucosidase inhibitory potential when compared to others i.e., IC50 of H6 = 60.89 μM and IC50 of acarbose = 51.42 μM. We measured the antioxidant potential of H1–H6 exploring 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO) and ferric reducing ability power (FRAP) assays. The DPPH as well as NO radical scavenging assay showed that all the compounds exhibited excellent antioxidant results with some of the compounds surpassing catechin (reference drug). Compound H5 with IC50 values of 30.32 mM and 31.73 mM outshined catechin with IC50 values of 31.17 mM and 140.62 mM for DPPH and NO assays respectively. All the compounds fell within the threshold of Lipinski’s Ro5 projecting them as orally bioavailable and less toxic future therapeutics.