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Borocarbonitride (BCN) materials, emerging as metal-free catalysts, have garnered considerable interest owing to their plentiful availability; their impressive tolerance across diverse pH levels; and the tunable capability of their B, N-doped carbon network and band structures. These materials exhibit impressive performance in various catalytic reactions related to energy conversion and organic synthesis. This review summarizes the most recent advancements in the synthesis methods and catalytic applications of BCN catalysts and discusses the synergistic promotion between B and N heteroatoms embedded within the carbon network structures in catalytic processes, thereby offering advanced catalytic processes and perspectives on comprehending the underlying reaction mechanisms. The review begins with an introduction to the structure and theoretical simulation of BCN materials, followed by a summary and analysis of various synthesis methods reported in the most recent years. Subsequently, we offer a detailed discussion regarding real active site structures present on the surface of BCN materials in oxidative dehydrogenation, reduction reactions and energy conversion processes (water splitting, CO2 reduction, oxygen reduction reaction, and N2 reduction reaction) as well as photocatalytic reactions (H2 evolution, CO2 reduction, and organic synthesis), contributing novel insights into the nature of reactive sites involved and band characteristics. Ultimately, the existing issues and challenges encountered in current BNC catalyst research are highlighted, and accordingly, promising research directions for future efforts are proposed. [ABSTRACT FROM AUTHOR]

We prepared an organically templated magnet, (enH2)0.5VPO4OH (enH2 = diprotonated ethylenediamine), hydrothermally and characterized its crystal structure by powder X-ray diffraction and Fourier-transform infrared spectroscopy, and its physical properties by magnetization, specific heat and nuclear magnetic resonance measurements and density functional theory calculations. (enH2)0.5VPO4OH consists of uniform chains of V3+ (d2, S = 1) ions and exhibits Haldane magnetism with spin gap Δ = 59.3 K from the magnetic susceptibility χ(T) at μ0H = 0.1 T, which is reduced to 48.4 K at μ0H = 9 T according to the 31P shift. The NMR data evidence the formation of a spin-glass state of unpaired S = 1/2 spins at TS–G ≈ 3 K and indicate that the Haldane S = 1 spin chain segments are much longer in the organically templated magnet (enH2)0.5VPO4OH than in the ammonium counterpart NH4VPO4OH. The single-ion anisotropy D and the interchain exchange J′ in (enH2)0.5VPO4OH and NH4VPO4OH were estimated in density functional calculations to find them very weak compared to the intrachain exchange J. [ABSTRACT FROM AUTHOR]

Controlling the spatial morphology of the nanorods (NRs) in a polymer matrix and understanding the structure–property relationship are crucial for fabricating high-performance polymer nanocomposites (PNCs). By employing molecular dynamics simulations, we systematically studied the structural and mechanical properties of NR filled PNCs. The simulated results showed that the NRs gradually self-assembled into a three-dimensional (3D) network upon increasing the NR–NR interaction strength. The generated 3D NR network transferred loads along the NR backbone, differing from the well dispersed system which transfers loads between NRs and nearby polymer chains. Increase of the nanorod diameter or NR content further enhanced the PNCs by improving the NR network integrity. These findings provide insights into the reinforcement mechanism of NRs toward polymer matrices and provide guidance for designing PNCs with excellent mechanical performance. [ABSTRACT FROM AUTHOR]

Four sulfonamide derivatives with a methoxyphenyl moiety, namely N-{4-[(2-methoxyphenyl)sulfamoyl]phenyl}acetamide (1a), N-{4-[(3-methoxyphenyl)sulfamoyl]phenyl}acetamide (1b), 4-amino-N-(2-methoxyphenyl)benzenesulfonamide (2a) and 4-amino-N-(3-methoxyphenyl)benzenesulfonamide (2b), have been synthesized and characterized physiochemically by CHNS, MS, FT-IR, 1H NMR, 13C NMR, PXRD and TG methods. Crystal structures were determined by SC-XRD and their conformational and noncovalent interaction properties were examined by both experimental and theoretical (HS, MEPS, NBO, dimerization energy, QTAIM) methods. The conformational flexibility of the bridge connecting two phenyl rings was studied and minimum-energy conformations were theoretically found. The packing architecture and hydrogen bond networks were described by graph set notation. Hirshfeld surface analysis revealed regions of stronger contacts and allowed us to indicate the relative contributions of different noncovalent contacts in the crystal packing. MEPS calculations helped to distinguish the electron rich and electron poor regions and to find the best H-bond donors and acceptors. The use of the QTAIM method enabled us to explain the influence of functional groups and molecular arrangement on the strength of noncovalent interactions in the crystals and overall packing efficiency. [ABSTRACT FROM AUTHOR]

In the present attempt, a Dy, W co-doped La2Mo2O9 (LMX) system is explored to understand the order–disorder phase transition, dynamical disorder state and their influence on the oxy-ion diffusion mechanism. The X-ray diffraction study confirms the co-dopant induced suppression of the order–disorder phase transition temperature of LMX. The oxygen ion diffusion in the LMX matrix is through intrinsic oxygen vacancies. Disorder oxygen vacancies enhance the degree of freedom of oxy-ion diffusion; these are related to the dynamical disorder states in LMX. These disorder states are demonstrated by high temperature Raman spectra. Dynamical disordering of oxygen vacancies in co-doped LMX systems is revealed by studying the rate of change of intensity of the Mo–O bond vibration as a function of temperature; non-uniformity in the rate of change of intensity is correlated to dynamical disorder. The dielectric relaxation studied by using dielectric loss spectra reveals a single relaxation peak for the pure-LMX system, while two dielectric relaxation peaks are revealed for doped LMX systems. Oxygen vacancy reorientation associated with dielectric relaxation is correlated to the diffusion process between O(1) → O(2) and O(1) → O(3) oxygen ion-vacancy exchange sites in doped LMX systems, while it is O(1) through orderly arranged oxygen vacancies in the pure LMX system. To ascertain the relaxation dynamics of the bulk system, electric modulus formalism is helpful, M′′ data are fit by the Bergman function represented by the Kohlrausch–Williams–Watts (KWW) formula and non-Debye type relaxation is revealed for all systems. The activation energy of oxy-ion diffusion is reduced by a co-doping effect. Ionic conductivity extracted from complex impedance spectra indicates that oxy-ion conductivity in a co-doped LMX system is improved almost one order as compared to the pure system. The study reveals that a co-doped LMX system has the potential to be used as electrolytes for intermediate temperature solid oxide fuel cells (400–700 °C, IT-SOFCs). [ABSTRACT FROM AUTHOR]

The effect of halogen substitution in fluorescent BODIPY species was evaluated in the context of staining lipids in situ within brain tissue sections. Herein we demonstrate that the halogenated species maintain their known in vitro affinity when applied to detect lipids in situ in brain tissue sections. Interestingly, the chlorine substituted compound revealed the highest specificify for white matter lipids. Furthermore, the halogen substituted compounds rapidly detected lipid enriched cells, in situ, associated with a case of brain pathology and neuroinflammation. [ABSTRACT FROM AUTHOR]

Sulfamethoxazole (SMZ) is a synthetic broad-spectrum antibiotic of biopharmaceutical classification system (BCS) class IV, with both low solubility and permeability, requiring probably higher drug doses in orally-administered formulations to promote an expected systemic absorption. To overcome such limitations and especially to increase its solubility, this study has a main purpose of the development of novel optimized crystalline forms of SMZ. Herein, two crystalline salts of SMZ (SMZBr and SMZNO3) have been synthesized from solution crystallization and characterized using X-ray (single and powder), spectroscopic (infrared, FT-IR) and thermal (DSC and TGA) techniques. Furthermore, a solubility study was performed in pure water and compared with the SMZCl salt and SMZ form I. It was observed that the SMZBr salt exhibits phase stability in water media and shows enhanced solubility compared to the SMZCl salt and SMZ form I. Additionally, a qualitative litmus paper test was employed to verify the volatiles released during the thermal drug degradation. [ABSTRACT FROM AUTHOR]

The asymmetric Michael addition of diphenylbutazone and its analogues to α,β-unsaturated 2-acyl imidazoles has been developed with a chiral-at-metal Rh(iii) complex as a catalyst. The corresponding adducts were obtained in good yields (89–98%) with excellent enantioselectivities (up to ＞99%). The reaction can be conducted on a gram-scale with a low catalyst loading (0.04 mol%) without impacting its efficiency. Moreover, the adducts can be converted into other useful synthetic building blocks. [ABSTRACT FROM AUTHOR]

A series of TF4 and ZF5 molecules (T = Si, Ge, Sn and Z = P, As, Sb) were allowed to engage in tetrel and pnicogen bonds, respectively, with NH3, pyrazine, and HCN. The interaction energies are quite large, approaching 50 kcal mol−1 in some cases. The formation of each complex is accompanied by substantial geometrical deformation of the Lewis acid to accommodate the approaching base. The energy associated with this monomer rearrangement is the largest for the smaller central atoms Si and P, where it exceeds 20 kcal mol−1. The total reaction energy of binding, which takes this distortion energy into account, is thus significantly lower than the interaction energy, although remaining quite high, particularly for the larger Sn and Sb central atoms. The tetrel and pnicogen bonds can still form even if the Lewis acid is not permitted to adjust its internal geometry, but they are drastically weakened, dropping by as much as 95%. The monomer rearrangement also aids in the binding by intensifying its σ-hole by a factor of 1.5–2.9. [ABSTRACT FROM AUTHOR]

The purpose of this survey is to examine the crystal packing of bent metallocenes, namely, group IV, V and VI biscyclopentadienyl dihalides and dihydrides, first synthesized in the late 1950s. This analysis is based on the present knowledge on new types of intermolecular contacts such as halogen and C–H…π interactions as well as dihydrogen bonds. Results are also supported by ab initio calculations that provide information on electrostatic charge distributions, in particular the effect of two V-shaped metal–halogen bonds on the molecular electron density distribution. Type I halogen interactions do not appear to be affected by this feature, specifically the geometric parameters and variation of atom polarizability, but the resultant electronic density distribution precludes the presence of Type II halogen bonds. Special attention is given to the competition among hydrogen and halogen interactions, in particular its influence on the nature and geometric orientations of the different supramolecular motifs and, ultimately, on the space groups observed for each crystal. [ABSTRACT FROM AUTHOR]

Divalent metal complexes of malonate with aminoguanidine possessing (AmgH)2[M(mal)2(H2O)2] [M = Co (1), Ni (2) or Zn (3); mal = malonate anion and AmgH = aminoguanidinium cation] stoichiometry and their solid solutions, (AmgH)2[Ni0.5Co0.5(mal)2(H2O)2] (4) and (AmgH)2[M1/3Co2/3(mal)2(H2O)2] [where M = Ni (5) or Zn(6)], were prepared and characterized by analytical, thermal and powder X-ray diffraction studies. The crystal and molecular structures of both cobalt and nickel compounds were isomorphic, crystallizing in the triclinic space group P1. The complexes exhibit similar modes of endo-followed by exothermic decomposition to produce respective metal oxides below 550 °C. Metal cobaltites, MCo2O4where M = Ni and Zn, were obtained from the above solid solutions as decomposition residues by heating at 600, 700 and 800 °C in a silica crucible for 3 h. Spinel oxides nanoparticles were characterized by infrared spectra, powder X-ray diffraction patterns, scanning electron microscope coupled with energy dispersive X-ray analysis and transmission electron microscope studies. [ABSTRACT FROM AUTHOR]