Computational and Theoretical Chemistry最新文献_第10页

First-principles study of hydrogen adsorption energy and preferred storage site in MgNi alloys MgNi合金中氢吸附能和优选储存位置的第一性原理研究

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-21 DOI: 10.1016/j.comptc.2025.115600

Huan Wang , Changli Shi , Zihe Cao , Xiaolu Chen , Qiguo Zhang , Gangjun Gong , Qiang Lu , Xinhua Yuan , Bing Zhang

MgNi alloys are promising candidates for hydrogen storage materials due to their significant potential in sustainable energy technologies. However, accurately predicting hydrogen adsorption energies and identifying optimal storage sites remain critical challenges. This study evaluates the performance of two DFT exchange-correlation functionals (PBE and SCAN) and assesses the effects of Hubbard U correction and van der Waals interaction on MgNi alloys. The results demonstrate that SCAN significantly outperforms PBE in predicting hydrogen adsorption energies due to its consideration of orbital kinetic energy density. Variations in the contributions of Hubbard U and vdW interactions are observed across different storage sites. Based on parameters such as volume change rate, adsorption energy, NiH bond length and ICOHP, the H2 site is identified as the preferred storage site. These findings highlight the importance of theoretical parameters in optimizing MgNi alloy systems, providing insights for advancing efficient hydrogen storage materials and supporting sustainable energy technologies.

MgNi合金因其在可持续能源技术中的巨大潜力而成为储氢材料的有希望的候选者。然而，准确预测氢吸附能和确定最佳储存地点仍然是关键的挑战。本研究评估了两种DFT交换相关泛函（PBE和SCAN）的性能，并评估了Hubbard U校正和van der Waals相互作用对MgNi合金的影响。结果表明，由于考虑了轨道动能密度，SCAN在预测氢吸附能方面明显优于PBE。在不同的储存地点观察到Hubbard U和vdW相互作用的贡献的变化。基于体积变化率、吸附能、NiH键长、ICOHP等参数，确定H2位点为首选存储位点。这些发现突出了理论参数在优化MgNi合金系统中的重要性，为推进高效储氢材料和支持可持续能源技术提供了见解。

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引用次数: 0

Quantum chemical studies on chelator combination in Hg2+, Pb2+ and UO22+ poisonings 螯合剂组合对Hg2+、Pb2+和UO22+中毒的量子化学研究

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-20 DOI: 10.1016/j.comptc.2025.115599

Xiaoyan Cao , Michael Dolg

A systematic quantum chemical investigation was conducted at the density functional theory level, employing relativistic pseudopotentials for Hg, Pb, and U, to investigate the detoxification from heavy metal ions (M²⁺ = Hg²⁺, Pb²⁺, and UO₂²⁺) using the chelator combination of H₂BAL (British Anti-Lewisite) and H₄DMSA (meso-dimercaptosuccinic acid). Target compounds for detoxification included model systems of a classical zinc-finger protein (ZnF) and calmodulin (CaM), where Zn²⁺and Ca²⁺ were replaced by a poisonous M²⁺ ion, i.e., Hg²⁺-ZnF, Pb²⁺-ZnF, Pb²⁺-CaM, and UO₂²⁺-CaM. It was found that M²⁺ coordinates with up to two DMSA units to form stable complexes, whereas for BAL the coordination numbers were two for Hg²⁺ and Pb²⁺, and four for UO₂²⁺. The calculated negative changes of Gibbs free energies ΔG in the metal-ligand exchange reactions between M²⁺-ZnF and neutral/anionic BAL indicate thermodynamically spontaneous processes. Our results demonstrate that the H₂BAL/H₄DMSA combination might be a promising strategy for uranyl (UO₂²⁺) detoxification.

利用Hg、Pb和U的相对论赝势，在密度泛函理论水平上进行了系统的量子化学研究，研究了H₂BAL （British Anti-Lewisite）和H₄DMSA （meso- dimercapto琥珀酸）的螯合剂组合对重金属离子（M2+ = Hg2+、Pb2+和UO22+）的解毒作用。解毒的目标化合物包括经典锌指蛋白（ZnF）和钙调蛋白（CaM）的模型系统，其中Zn2+和Ca2+被有毒的M2+离子取代，即Hg2+-ZnF， Pb2+-ZnF， Pb2+-CaM和UO22+-CaM。发现M2+与2个DMSA单元配位形成稳定的配合物，而对于BAL， Hg2+和Pb2+的配位数为2，UO22+的配位数为4。计算得到的M2+-ZnF与中性/阴离子BAL之间的金属配体交换反应中Gibbs自由能ΔG的负变化表明了热力学自发过程。我们的研究结果表明，H2BAL/H4DMSA组合可能是一种有希望的铀酰（UO22+）解毒策略。

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引用次数: 0

Predicting protic redox potentials with computational error bars 用计算误差条预测质子氧化还原电位

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-19 DOI: 10.1016/j.comptc.2025.115590

Lachlan O. Smith, Deborah L. Crittenden

Design of redox-active species for applications such as sensing and energy storage requires reliable prediction of redox potentials, frequently in protic environments. However, this is complicated by the fact that multiple reaction pathways are possible, which cannot be easily elucidated experimentally. Computational assignment of redox reaction mechanisms by matching computed and measured redox potentials is an enticing possibility, but demands careful treatment of computational uncertainties because these may be of the same order of magnitude as mechanism-dependent differences. Here, we introduce a new scheme for estimating computational “error bars” by identifying density functionals whose predicted redox potentials systematically bound experimental data. We demonstrate that the bounding behaviour of hybrid functionals may be tuned by altering the proportion of Hartree–Fock exchange, while generalised gradient functionals are more sensitive to the nature and form of the specific gradient corrections applied to correct for the local density approximation.

用于传感和储能等应用的氧化还原活性物质的设计需要可靠的氧化还原电位预测，通常在质子环境中。然而，这是复杂的事实，多种反应途径是可能的，这是不容易阐明的实验。通过匹配计算和测量的氧化还原电位来计算氧化还原反应机制是一种诱人的可能性，但需要仔细处理计算的不确定性，因为这些不确定性可能与机制相关的差异具有相同的数量级。在这里，我们引入了一种新的方案，通过识别密度泛函来估计计算“误差条”，其预测的氧化还原电位系统地结合了实验数据。我们证明了混合泛函的边界行为可以通过改变Hartree-Fock交换的比例来调整，而广义梯度泛函对用于校正局部密度近似的特定梯度修正的性质和形式更为敏感。

引用次数: 0

Theoretical insights into SOMO–HOMO conversion and luminescence in boracyclic radicals 硼环自由基中SOMO-HOMO转换和发光的理论见解

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-19 DOI: 10.1016/j.comptc.2025.115592

Yanbin Zhu, Hongbo Li, Shoufeng Zhang, Jin Zhou, Li Zhang

Luminescent radicals exhibiting SOMO–HOMO conversion (SHC) have attracted considerable interest due to their distinctive photophysical properties. This work presents a computational study on a series of boracyclic-based radicals, exploring how π-conjugation and electron-donating/withdrawing groups tune electronic structure and radiative and nonradiative decay rates. Calculations reveal that all designed radicals display SHC behavior, with luminescence originating from the D₁ state. Natural Bond Orbital (NBO) and Atoms-in-Molecules (AIM) analyses indicate pronounced intramolecular charge transfer (ICT) and noncovalent interactions stabilized by boron–oxygen coordination. Electron-donating substituents enhance electron delocalization, promoting radical aromaticity and stability. In contrast, nonradiative decay is modulated by structural relaxation and hybridized charge-transfer and local excitation (CT–LE) states. These results underscore the critical role of π-conjugation, number of boracyclic units, and substituent electronic nature in tuning electronic properties and recombination processes. The insights offer guidelines for enhancing photostability and broadening photofunctionality in radical-based luminescent systems.

具有SOMO-HOMO转换的发光自由基（SHC）由于其独特的光物理性质而引起了人们的广泛关注。本文对一系列硼环基自由基进行了计算研究，探索π共轭和供/吸电子基团如何调节电子结构和辐射和非辐射衰变速率。计算表明，所有设计的自由基都显示出SHC行为，发光源自D₁状态。自然键轨道（NBO）和分子内原子（AIM）分析表明，分子内电荷转移（ICT）和硼氧配位稳定的非共价相互作用明显。给电子取代基增强电子离域，促进自由基芳构性和稳定性。相反，非辐射衰变是由结构弛豫和杂化电荷转移和局部激发（CT-LE）状态调制的。这些结果强调了π共轭、硼环单位数和取代基电子性质在调整电子性质和复合过程中的关键作用。这些见解为提高自由基基发光系统的光稳定性和扩大光功能提供了指导。

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引用次数: 0

Acrolein detection in gaseous, aqueous, and oil phases through CaO, MgO, and BeO nanocages based on DFT 基于DFT的CaO、MgO和BeO纳米笼检测气相、水相和油相丙烯醛

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-18 DOI: 10.1016/j.comptc.2025.115594

Khalid Mujasam Batoo , Pawan Sharma , Muhammad Farzik Ijaz , Abhishek Kumar , Syeda Wajida Kazmi , Forat H. Alsultany , Iman Samir Alalaq , Ruaa Sattar , Munthir Abdulwahid Abdulhussain , Merwa Alhadrawi

This paper reports a Density Functional Theory (“DFT”) assessment of “CaO”, “MgO”, and “BeO” nanocages for acrolein (“AC”) detection, analyzing various adsorption configurations and Frontier Molecular Orbital (“FMO”) variations. The calculated interaction strength follows the order “AC”@”CaO" > “AC”@”MgO" > “AC”@”BeO". Electrical conductivity analysis reveals that the “BeO” nanocage possesses the maximum conductivity, surpassing “MgO” and “CaO”. The optimization of “AC” desorption recovery time was also performed. Crucially, the analysis of complexes in different media demonstrated that structural stability is significantly higher in aqueous media (ΔG_W analysis) compared to the oily phase (ΔG_O), confirming efficient capture across gaseous, aqueous, and oily phases. The investigation of “HOMO-LUMO" levels and the energy gap further substantiates the viability of these oxide nanocages as high-performance sensors for toxic “AC” molecules.

本文报道了密度泛函理论（DFT）评估“CaO”，“MgO”和“BeO”纳米笼用于丙烯醛（“AC”）检测，分析了各种吸附构型和前沿分子轨道（“FMO”）变化。计算得到的相互作用强度顺序为“AC”@“CaO”>；“AC”@“MgO”>；“AC”@“BeO”。电导率分析表明，“BeO”纳米笼的电导率最高，超过了“MgO”和“CaO”。并对“AC”解吸恢复时间进行了优化。至关重要的是，对不同介质中配合物的分析表明，与油相（ΔG_O）相比，水相（ΔG_W分析）中的结构稳定性要高得多，这证实了气相、水相和油相的有效捕获。“HOMO-LUMO”水平和能隙的研究进一步证实了这些氧化物纳米笼作为有毒“AC”分子的高性能传感器的可行性。

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引用次数: 0

Exploring the stability and reactivity of Ga, In, and Hg interactions with TNT: Insights from DFT calculations 探索Ga， In和Hg与TNT相互作用的稳定性和反应性：来自DFT计算的见解

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-17 DOI: 10.1016/j.comptc.2025.115596

Jerimiah A. Zamora, Michelle L. Pantoya, Adelia J.A. Aquino

This work models the interaction of Ga, In, and Hg with the nitroaromatic explosive 2,4,6-trinitrotolulene (TNT) using density functional theory (DFT). The electronic properties of Ga and In are hypothesized to destabilize TNT and may induce decomposition when in atomic scale proximity. TNT configurations (monomer, dimer, and trimer) were examined. The formation energies (ΔE_f), enthalpies (ΔH_f), and Gibbs free energies (ΔG_f), energy gap (Δε), charge analysis (NPA), deformation energies (E_d), stabilization energy (E⁽²⁾), and weak interaction (NCI) are computed for all complexes. Ga-(TNT)_n and In-(TNT)_n complexes show enhanced reactivity across all configurations, with decreasing energy gaps as n increases, consistent with prior DFT studies on Al–TNT complexes. NPA, E⁽²⁾, and NCI analyses indicate charge transfer, orbital overlap, and steric effects driving Ga and In complexes formation, but not for Hg. Overall, thermodynamic results suggest Ga and In may destabilize TNT, offering potential for applications that neutralize its explosive potential.

本文利用密度泛函理论（DFT）模拟了Ga、In和Hg与硝基芳香炸药2,4,6-三硝基甲苯（TNT）的相互作用。假设Ga和In的电子性质会破坏TNT的稳定性，并可能在原子尺度接近时引起分解。研究了TNT的构型（单体、二聚体和三聚体）。计算了所有配合物的形成能（ΔEf）、焓（ΔHf）、吉布斯自由能（ΔGf）、能隙（Δε）、电荷分析（NPA）、变形能（Ed）、稳定能（E(2)）和弱相互作用（NCI）。Ga-(TNT)n和In-(TNT)n配合物在所有构型中都表现出增强的反应性，随着n的增加，能隙减小，这与之前Al-TNT配合物的DFT研究结果一致。NPA、E(2)和NCI分析表明，电荷转移、轨道重叠和空间效应驱动了Ga和In络合物的形成，但对Hg没有影响。总的来说，热力学结果表明，Ga和In可能会破坏TNT的稳定，为中和其爆炸潜力提供了潜在的应用。

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引用次数: 0

Atomic-level insights into the oxidation of SWCNTs based on reactive molecular dynamics simulations 基于反应分子动力学模拟的SWCNTs氧化的原子水平见解

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-14 DOI: 10.1016/j.comptc.2025.115598

Liang Song , Ze-Chun Lin , Xing-Long Chen , Yun-Hui Hou , Min Li , Xiao Ma , Tao Fang , Fang-Chao Hou , Jing Sun

The oxidation behavior of SWCNTs by O₂ was examined using the ReaxFF molecular dynamics simulations. Results show that cap-ends serve as preferred targets for the attack of O₂ molecules due to their high curvature and exposed carbon atoms. Local oxidation of SWCNT ends leads to the formation of metastable pores and epoxy groups, making it challenging for the end cap to close and restructure. As the temperature rises to 4750–5250 K, Y-shaped carbon chain nodes spontaneously rearrange into 5-membered rings. This ring condensation gradually facilitates the closure of the hemispherical carbon cap, although oxygen depletion limits extensive reconstruction. An increase in O₂ concentration promotes the accumulation of carbonyl and epoxy groups. CO emerges as the dominant small molecule product, with its yield increasing in tandem with temperature and oxygen concentration. In contrast, the amount of CO₂ formed is minimal and occurs only in (16,16) SWCNTs.

利用ReaxFF分子动力学模拟研究了SWCNTs被O2氧化的行为。结果表明，由于其高曲率和暴露的碳原子，帽端成为O2分子攻击的首选目标。swcnts末端的局部氧化导致亚稳孔和环氧基团的形成，使得末端帽关闭和重组变得困难。当温度升高到4750 ~ 5250 K时，y型碳链节点自发重排成5元环。这种环状凝聚逐渐促进了半球形碳帽的闭合，尽管氧的耗尽限制了广泛的重建。O2浓度的增加促进羰基和环氧基的积累。CO是主要的小分子产物，其产率随温度和氧浓度的增加而增加。相比之下，CO2的形成量是最小的，并且只发生在（16,16）SWCNTs中。

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引用次数: 0

Atomic radial correlation energy density components 原子径向相关能量密度分量

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-14 DOI: 10.1016/j.comptc.2025.115597

Ibrahim E. Awad , Abd Al-Aziz A. Abu-Saleh , Gurleen Cheema , Joshua W. Hollett , Raymond A. Poirier

The components of the radial correlation energy density are calculated and analyzed for the atoms from He to Ar. The components include the nucleus-electron potential correlation energy density, the kinetic correlation energy density and the electron–electron potential correlation energy density. The necessary correlated one and two-electron density matrices are obtained from the Extrapolated-Full-Configuration-Interaction (exFCI) wave function where the reference wave function is restricted Hartree–Fock (RHF) or restricted open-shell Hartree–Fock (ROHF) depending on whether the atom is closed or open-shell. The accuracy associated with integrating the HF and exFCI energy density components, and the correlation energy density components, is evaluated on the SG-1 and SG-2 atomic grids. The SG-1 grid provides atomic energies that are accurate to about 1 kJ mol⁻¹, with the exception of the kinetic energy. The SG-2 grid is required for the analysis of atomic kinetic energies and more subtle energetic effects. There is also a significant amount of integration error cancellation in the correlation energy densities. The radial correlation energy densities display notable shell structure, and there is a substantial difference between the

α

and

β

-electron correlation energy densities for the open-shell atoms.

计算并分析了He - Ar原子径向相关能密度的组成，包括核-电子势相关能密度、动力学相关能密度和电子-电子势相关能密度。从外推全构型相互作用（exFCI）波函数中得到必要的相关单电子和双电子密度矩阵，其中参考波函数是受限Hartree-Fock （RHF）或受限开壳Hartree-Fock (ROHF)，取决于原子是闭合还是开壳。在SG-1和SG-2原子网格上对HF和exFCI能量密度分量以及相关能量密度分量的积分精度进行了评估。SG-1网格提供的原子能量精确到1 kJ mol−1左右，动能除外。SG-2网格是分析原子动能和更微妙的能量效应所必需的。在相关能量密度中也有大量的积分误差抵消。径向相关能密度表现出明显的壳层结构，开壳原子的α -电子相关能密度与β-电子相关能密度存在较大差异。

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引用次数: 0

Study on water-acid synergistic effects in the diffusion of natural ester-mineral oil blends by molecular dynamics simulation 用分子动力学模拟研究天然酯-矿物油共混物在扩散过程中的水-酸协同效应

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-14 DOI: 10.1016/j.comptc.2025.115595

Yujing Tang, Yanan Tang, Lei Zhang, Qiang Ou, Qi Wang

The moisture and small acid in insulation oil accelerate the aging of transformer oil paper insulation, which seriously threatens the safe operation of the transformer. In this work, the diffusion mechanism of natural ester oil-paper interface model (zwy), mineral oil-paper interface model (kwy) and natural ester blend mineral oil-paper interface model (hhy) under the synergistic action of water and formic acid were studied by molecular dynamics. The mean square displacement, radial distribution function, interaction energy, free volume and hydrogen bond were analyzed. The results show that the diffusion rates for water and formic acid are between 4.8 and 7.3 times greater in the hhy system blend compared to zwy system. When compared to the kwy system, the diffusion rates in the hhy are 0.7 and 1.2 times. Meanwhile, compared to kwy and hhy, zwy is more likely to form hydrogen bonding networks. At the same time, the movement of water molecules and formic acid in zwy was restricted, and the free volume fraction was relatively low. When the temperature rises from 298 K to 393 K, the breaking rates of kwy, zwy, and hhy hydrogen bonds were 4.7 %, 5.6 %, and 3.2 %, respectively. The results provide a theoretical basis and microscopic mechanism for the diffusion mechanism of water and small acid molecules in oil paper insulation systems.

绝缘油中的水分和小酸加速了变压器油纸绝缘的老化，严重威胁到变压器的安全运行。本文采用分子动力学方法研究了天然酯油纸界面模型（zwy）、矿物油纸界面模型（kwy）和天然酯混合矿物油纸界面模型（hhy）在水和甲酸协同作用下的扩散机理。分析了均方位移、径向分布函数、相互作用能、自由体积和氢键。结果表明，在hhy体系中，水和甲酸的扩散速率是zwy体系的4.8 ~ 7.3倍。hhy体系的扩散速率是kwy体系的0.7倍和1.2倍。同时，与kwy和hhy相比，zwy更容易形成氢键网络。同时，水分子和甲酸在zwy中的运动受到限制，自由体积分数相对较低。当温度从298 K升高到393 K时，kwy、zwy和hhy氢键断裂率分别为4.7%、5.6%和3.2%。研究结果为油纸绝缘体系中水和酸小分子的扩散机理提供了理论依据和微观机理。

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引用次数: 0

Rational design and excited-state properties study of efficient hot exciton luminescent materials 高效热激子发光材料的合理设计与激发态特性研究

IF 3 3区化学 Q3 CHEMISTRY, PHYSICAL

Computational and Theoretical Chemistry

Pub Date : 2025-11-12 DOI: 10.1016/j.comptc.2025.115593

Peng-Yuan Li , Fu-Quan Bai

Conventional TADF materials face a fundamental trade-off between small S₁-T₁ energy gap and fast S₁ radiative decay due to S₁'s dual role in RISC and emission. To address this conflict, we theoretically designed a series of novel ‘donor-anthracene-acceptor’ molecules via excited-state kinetics regulation and multi-parameter optimization. All molecules exhibit distinct T₂ excitation channels, decoupling T₂ → S₁ RISC from S₁ → S₀ emission. This strategy holds the potential for independent control of exciton utilization and luminescence intensity. DFT calculations reveal how the anthracene-donor/acceptor dihedral angle critically influences S₁-T₂ SOC, revealing a structure-property relationship for SOC tuning. Our calculations predict that the optimized candidate C4 would significantly suppress T₂ → T₁ internal conversion, with a predicted T₂ lifetime of 183 ns that could facilitate efficient spin-flip. This work proposes promising theoretical candidates for efficient hot exciton emitters and provides a computational framework for guiding the precise control of exciton kinetics via systematic excited-state analysis.

由于S1在RISC和发射中的双重作用，传统的TADF材料面临着S1- t1小能隙和快速S1辐射衰减之间的基本权衡。为了解决这一矛盾，我们通过激发态动力学调节和多参数优化，从理论上设计了一系列新的“供体-蒽-受体”分子。所有分子都表现出不同的T2激发通道，将T2→S1的RISC与S1→S0的发射解耦。这种策略具有独立控制激子利用和发光强度的潜力。DFT计算揭示了蒽-给体/受体二面角如何严重影响S1-T2荷电性，揭示了荷电性调谐的结构-性质关系。我们的计算预测优化后的候选C4将显著抑制T2→T1的内部转换，预计T2寿命为183 ns，可以促进有效的自旋翻转。这项工作提出了有效的热激子发射的有前途的理论候选人，并提供了一个计算框架，指导激子动力学的精确控制，通过系统的激发态分析。

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引用次数: 0