Journal of Chemical Sciences最新文献

{"title":"From density functional theory to spin Hamiltonians: Magnetism in (d^5) honeycomb compound OsCl(_3)","authors":"Ritwik Das,&nbsp;Indra Dasgupta","doi":"10.1007/s12039-025-02416-4","DOIUrl":"10.1007/s12039-025-02416-4","url":null,"abstract":"<p>Magnetism in strongly correlated honeycomb systems with <span>(d^5)</span> electronic configuration has garnered significant attention due to its potential to realize the Kitaev spin liquid state, characterized by exotic properties. However, real materials exhibit not only Kitaev exchange interactions but also other magnetic exchanges, which may drive the transition from a spin liquid phase to a long-range ordered ground state. This work focuses on modelling the effective spin Hamiltonian for two-dimensional (2D) honeycomb magnetic systems with <span>(d^5)</span> electronic configurations. The Hubbard–Kanamori (HK) Hamiltonian equipped with spin-orbit coupling and electron correlations is considered where on-site energies and hopping parameters, preserving the crystal symmetry are extracted from the first principle density functional theory (DFT) calculations. Exact diagonalization (ED) calculations for the HK Hamiltonian on a two-site cluster are performed to construct the effective magnetic Hamiltonian. The ground-state magnetic properties are explored using the semi-classical Luttinger–Tisza approach. As a representative case, the magnetic ground state of the <span>(d^5)</span> honeycomb system OsCl<span>(_3)</span> is investigated, and the variation of magnetic exchange parameters with respect to the correlation strength <i>U</i> and Hund’s coupling <span>(J_{text{H}})</span> is analysed. The magnetic ground state exhibits zigzag antiferromagnetic ordering for a chosen value of <i>U</i> and <span>(J_{text{H}},)</span> consistent with DFT results. This study provides an insight into the magnetism of OsCl<span>(_3)</span> and offers a computationally efficient alternative to traditional energy-based methods for calculating exchange interactions for strongly correlated systems.</p>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of electron-donating and withdrawing groups on diketopyrrolopyrrole-based dye sensitizers: A quantum chemical analysis","authors":"Anjali Devi Vasarla,&nbsp;Abhishek Dhar,&nbsp;Rahul Shukla,&nbsp;Anik Sen","doi":"10.1007/s12039-025-02414-6","DOIUrl":"10.1007/s12039-025-02414-6","url":null,"abstract":"<div><p>This study investigated diketopyrrolopyrrole-spacer-based dye sensitizers for dye-sensitized solar cells (DSSCs) applications, specifically the effects of electron-donating and electron-withdrawing groups on donor moieties. Using the computational methods, we evaluated the photophysical properties and efficiency metrics like light harvesting efficiency, electron injection efficiency, regeneration efficiency, and overall solar energy conversion efficiency, and compared them with the existing experimental results. Further, we have predicted better and more efficient dyes with small changes, like adding electron-donating groups on the para position of the donor moieties with density functional theory. The three donor groups: carbazole (CB), diphenylamine (DA), and indole (IN)- and their derivatives with electron-donating and electron-withdrawing substituents were examined.</p><h3>Graphical abstract</h3><p>Electron-donating groups on donor groups enhances the efficiency whereas electron-withdrawing groups reduces the efficiency.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A computational study of proton hopping induced energy stabilization of acetic acid networks","authors":"Anjalin Joy,&nbsp;Shyama Ramakrishnan,&nbsp;Padmesh Anjukandi","doi":"10.1007/s12039-025-02423-5","DOIUrl":"10.1007/s12039-025-02423-5","url":null,"abstract":"<p>Acetic acid is a fundamental organic molecule with widespread applications in industrial processes, biological systems, and catalysis. One key attribute of acetic acid is that it can form stable hydrogen-bonded networks in both the gas phase and the solution phase, particularly the cyclic dimer. Acetic acid molecules may form hydrogen bonds either with their kind or adjacent solvent molecules, depending upon the polarity of the solvents. The mechanism of cyclic dimer formation and the energetics associated with the concerted DPT (double proton transfer) in the cyclic dimer were investigated computationally by means of DFT (Density Functional Theory) and the NEB-TS (Nudged Elastic Band with TS optimization) methods. Additionally, structures of two hydrate complexes of acetic acid and two water-separated acetic acid dimers were isolated from the MD (molecular dynamics) simulation performed on an aqueous solution of acetic acid and the energy barriers associated with the concerted proton transfers were studied using the DFT and NEB-TS methods. The results provide insights into the potential energy surfaces associated with the concerted proton transfers in the hydrate complexes of acetic acid and the water-separated acetic acid dimers, shedding light on the increased kinetic hindrance along the concerned path.</p>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Current understanding of the microscopic effects of intrinsically disordered protein aggregates on the interfacial solvent properties","authors":"Asis K Jana,&nbsp;Prabir Khatua,&nbsp;Sanjoy Bandyopadhyay","doi":"10.1007/s12039-025-02426-2","DOIUrl":"10.1007/s12039-025-02426-2","url":null,"abstract":"<div><p>The misfolding and subsequent brain accumulation of two intrinsically disordered proteins, amyloid-beta (Aβ) and tau, are considered major hallmarks of Alzheimer's disease (AD), a neurodegenerative disorder characterized by cognitive decline and memory loss. Aβ accumulates extracellularly in the brain parenchyma, while tau aggregates intracellularly within neurons. Understanding the underlying molecular mechanisms is essential for uncovering the origins of AD and has remained an active area of research for over three decades, with the aim of developing therapeutics to mitigate or prevent disease progression. Our research group has made significant contributions over the years to explore the Aβ aggregation process, with particular emphasis on unraveling the role played by the solvent in guiding the process using large-scale atomistic molecular dynamics simulations. More recently, we have expanded our focus to probe the microscopic mechanism of aggregation of the tau protein. Some of the important findings that originated from our work have been presented in this review.</p><h3>Graphical abstract</h3><p>Alzheimer's disease is caused due to aggregation of two intrinsically disordered proteins (IDP), amyloid-β and tau. Simulation studies have unravelled that water plays a pivotal role in the aggregation process. A schematic image depicting water molecules confined within the core and at the surface of an IDP aggregate is shown.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular dynamics revelations of structures and dynamics of H3O+, Cu+ and Cu2+ ions within a model polymeric Nafion membrane","authors":"Antara Vaidyanathan,&nbsp;Pooja Sahu,&nbsp;Brahmananda Chakraborty,&nbsp;Sk Musharaf Ali","doi":"10.1007/s12039-025-02403-9","DOIUrl":"10.1007/s12039-025-02403-9","url":null,"abstract":"<div><p>The microscopic understanding of the morphology and ion/proton dynamics in hydrated Nafion systems is extremely essential for optimizing the efficiency of thermochemical/electrochemical processes like the Cu–Cl thermodynamic cycle for hydrogen generation. The present study addresses the gap in theoretical investigations on the structure and proton dynamics in aqueous Nafion systems, focusing on Cu⁺/Cu²⁺ and proton dynamics using robust MD simulations. We report a systematic investigation of the structure, transport and dynamics of protons and copper ions by varying water content, temperature and copper ion concentration. The present study captures the formation of continuous water channels within the hydrophobic Nafion matrix as observed in many experimental findings. Simulations are also conducted with 10% hydrated Nafion in contact with 11 N HCl and 1 M copper ions to represent the real composition of Cu–Cl electrolyzer. The MD analyses demonstrated that the highly acidic environment (11 N HCl) of the Cu–Cl electrolyzer would boost the swelling of Nafion membrane with reduced water–water interactions. On the other hand, the pairing of Cu–Cl ions would enhance the Nafion–hydronium ion interactions in the presence than in the absence of acid. The augmented interaction of hydronium ions with the sulfonic acid group of Nafion, would in due course, assist in faster transport of hydronium ions following Grotthuss mechanism. The hydrogen-bond life time of Nafion hydrated water was higher than that of bulk water due to the formation of separate water clusters within the Nafion membrane. The pores of Nafion allows only the transport of hydronium ions and water molecules whereas copper and chloride ions are restricted. The present findings on the structure and proton dynamics of the polymeric Nafion membranes might contribute towards the optimization of Cu–Cl electrolyzer for efficient and trouble free hydrogen production.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div><div><p>The effects of water content, temperature, presence of Cu⁺/Cu²⁺ ions and acidity in Nafion membrane were investigated. The increasing water content led to the formation of water channels within the membrane. Swelling, formation of channels and enhanced hydrogen bonding were observed at higher water content.</p></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational insights into tuning TADF properties via multiple donor–acceptor linkages","authors":"Jesni M Jacob,&nbsp;B Sandeep,&nbsp;K Prakash Kumar,&nbsp;Varatharaj Rajapandian,&nbsp;Mahesh Kumar Ravva","doi":"10.1007/s12039-025-02435-1","DOIUrl":"10.1007/s12039-025-02435-1","url":null,"abstract":"<div><p>Traditionally, thermally activated delayed fluorescence (TADF) molecular design has focused on donor–acceptor (D–A) structures. However, this study explores alternate molecular configurations that extend beyond the conventional models. Using density functional theory (DFT) and time-dependent DFT calculations, we systematically investigated the impact of various donor and acceptor arrangements, such as D_A, D_A_D, A_D_A, D_A_D_A, and D_A_A_D, on the TADF properties of emitters using 5,10-dihydrophenazine (DHPZ) as the donor and benzophenone (BP) as the acceptor. In tetrad systems, the electronic structure of TADF emitters strongly depends on the spatial arrangement of the donor and acceptor units. For instance, in the D_A_D_A configuration, the lowest three singlet and triplet states exhibit charge transfer character. In contrast, the D_A_A_D configuration reveals significant Frenkel-type character in T₃ and T₄ states. The involvement of these higher triplet states enhances the spin–orbit coupling value and improves the reverse intersystem crossing (RISC) rates. Additionally, the configuration of donor and acceptor units influences the number of potential RISC channels. Overall, the D_A_A_D configuration emerges as a promising design, demonstrating superior TADF performance through multiple efficient exciton utilization pathways (up to 10 RISC channels) and faster RISC rates (&gt; 10⁵ to 10⁸ s^–1) compared to D_A_D_A.</p><h3>Graphical abstract</h3><p> The D_A_A_D configuration emerged as a promising design, demonstrating superior TADF character through multiple efficient exciton utilization pathways (10 channels) and faster RISC (&gt; 10⁵ to 10⁸ s⁻¹) rates compared to D_A_D_A.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145315651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Why [BMIM]+[PF6]− is hydrophobic and [BMIM]+[BF4]− hydrophilic in nature? A quantum chemical investigation","authors":"SK. Samir Ahamed,&nbsp;Suman Chakrabarty,&nbsp;Ranjit Biswas","doi":"10.1007/s12039-025-02404-8","DOIUrl":"10.1007/s12039-025-02404-8","url":null,"abstract":"<div><p>Using the accurate quantum chemical calculations, the origin behind the hydrophobicity/hydrophilicity of two similar ionic liquids (ILs), 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]⁺[PF₆]⁻) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]⁺[BF₄]⁻) is thoroughly investigated. The structure of all the species and their corresponding interaction energies with water are computed by employing the wB97XD functional and 6-311G++(d,p) basis set. The use of the functional and basis set has been benchmarked either considering the experimental data or predictions from the sophisticated <i>ab initio</i> calculations. A continuum solvation model is utilized initially to understand the hydration (solvation) behaviour of the ILs as well as the hydration of the constituent ions. The explicit solvation has also been performed to monitor the effects of each molecular water addition to IL ion pairs and their anionic counterparts. This is done by calculating the interaction energy profiles as well as their charge distributions. It is found that anions and their charges transfer to cations or surroundings play a decisive role in this qualitatively different behaviour of these two ILs towards water. In addition, classical molecular dynamics simulations have been performed to investigate the hydration structure of the ions in the bulk water. The quantum chemical calculations presented here demonstrate the importance of anion-medium interactions in determining the hydrophobicity/hydrophilicity character of these two ILs.</p><h3>Graphical abstract</h3><p>This paper investigates quantum mechanical origin of hydrophobicity by considering two ionic liquids, differing only in anions, as representative systems. The non-ionic interaction was found play an important role. The Gradient isosurfaces and the corresponding RDG plots for both the represenattive ILs in water are also shown\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145315650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of substitution on some photophysical properties of pyridine: A comparison with benzene analogues","authors":"Nivedhitha Palanisamy,&nbsp;S Sudharshan,&nbsp;Sreeshakthi Varadharajan,&nbsp;Subrata Banik","doi":"10.1007/s12039-025-02421-7","DOIUrl":"10.1007/s12039-025-02421-7","url":null,"abstract":"<p>The effects of substitutions on pyridine for different photophysical properties, namely HOMO, LUMO energies, band gap, ionization potential, electron affinity, and excited state energies (S₁ and T₁) are studied systematically. A comparison with substituted benzene shows that the substitution of pyridine has significantly different influence on these molecular properties for a given electron-donating/withdrawing substituent. The molecular properties vary significantly with the position of the substitution with respect to the nitrogen atom of pyridine. For the substituents like −OH or −OMe, the electron donation ability through +R effect counters electron withdrawing ability through −I effect, depending on their attachment with respect to the nitrogen atom of pyridine. The study highlights the significance of substituent in modifying the electronic properties of organic materials. These insights are crucial for advancing the design of organic electronic materials, where pyridine plays an important role in electron transport.</p>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase-space Fisher information and Rényi entropy in the thermodynamic scheme of density functional theory","authors":"Á Nagy","doi":"10.1007/s12039-025-02413-7","DOIUrl":"10.1007/s12039-025-02413-7","url":null,"abstract":"<p>The link between the phase-space Fisher information and Rényi entropy is explored in the thermodynamic scheme of density functional theory. The momentum-space part of the phase-space Rényi entropy can be expressed with the phase-space Fisher information in the case of constant temperature. Both measures can be given by the kinetic energy. Moreover, in Coulomb systems they can be related to the total energy as well as energy differences, and excitation energies can also be provided by these information measures.</p><p>Link between the phase-space Fisher information and R´enyi entropy is established in the thermodynamic scheme of density functional theory. The position and momentum parts of the Rényi entropy are investigated in case of constant temperature. </p>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Excited-state hydrogen bond strengthening drives ultrafast electron transfer in coumarin 153/dimethylaniline complex: A TDDFT study","authors":"Li-lin Jiang,&nbsp;Wei-long Liu,&nbsp;Yun-fei Song,&nbsp;Gui-rong Wu","doi":"10.1007/s12039-025-02424-4","DOIUrl":"10.1007/s12039-025-02424-4","url":null,"abstract":"<div><p>The role of intermolecular hydrogen bonds in photoinduced electron transfer (PET) between coumarin 153 (C153) and <i>N</i>,<i>N</i>-dimethylaniline (DMA) was investigated using DFT and TDDFT. Calculations revealed that two intermolecular hydrogen bonds significantly strengthen in the excited state (S₂), with hydrogen-bond binding energy increasing from 8.24 kJ/mol to 157.35 kJ/mol, and dipole moment rising from 7.25 D to 23.43 D. Frontier molecular orbital analysis confirmed that the S₁ state is an intermolecular charge transfer (CT) state, facilitated by enhanced hydrogen bond coupling. Spectral shifts in C–H stretching vibrations validated hydrogen bond dynamics. These findings demonstrate that the reinforcement of hydrogen bonds in the excited state accelerates PET, offering valuable insights for the design of efficient photoactive materials.</p><h3>Graphical Abstract</h3><p>This study shows that the S excited state of the C153/DMA complex is a locally excited state on C153 with partial intramolecular charge transfer (CT) from N to the C=O group. The S₁ state, in contrast, is an intermolecular CT state involving photoinduced electron transfer (PET) from DMA to C153 and has low oscillator strength. Hydrogen bonds between molecules are stronger in the S₂ state, supporting this electron transfer. </p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":"137 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}