Journal of Chemical Physics最新文献_第7页

Phase behavior of x-shaped liquid crystalline macromolecules. x形液晶大分子的相行为。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0245343

Dan Wei, Zhijuan He, Yunqing Huang, An-Chang Shi, Kai Jiang

{"title":"Phase behavior of x-shaped liquid crystalline macromolecules.","authors":"Dan Wei, Zhijuan He, Yunqing Huang, An-Chang Shi, Kai Jiang","doi":"10.1063/5.0245343","DOIUrl":"https://doi.org/10.1063/5.0245343","url":null,"abstract":"X-shaped liquid crystalline macromolecules (XLCMs) are obtained by tethering two flexible end A-blocks and two flexible side B-blocks to a semiflexible R-block. A rich array of ordered structures can be formed from XLCMs, driven by the competition between the interactions between the chemically distinct blocks and the molecular connectivity. Here, we report a theoretical study on the phase behavior of XLCMs with symmetric and asymmetric side blocks by using the self-consistent field theory (SCFT). A large number of ordered structures, including smectic phases, simple and giant polygons, are obtained as solutions of the SCFT equations. Phase diagrams of XLCMs as a function of the total length and asymmetric ratio of the side chains are constructed. For XLCMs with symmetric side blocks, the theoretically predicted phase transition sequence is in good agreement with experiments. For XLCMs with a fixed total side chain length, transitions between layered structure to polygonal phases, as well as between different polygonal phases, could be induced by varying the asymmetry of the side chains. The free energy density, domain size, side chain stretching, and molecular orientation are analyzed to elucidate mechanisms stabilizing the different ordered phases.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 11","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143657392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emergent marginality in frustrated multistable networks. 受挫多稳定网络中的突现边缘性。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0255042

Dor Shohat, Yoav Lahini, Daniel Hexner

引用次数: 0

Structural effects of the insertion of large rings in two-dimensional networks. 在二维网络中插入大环的结构效应。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0252548

Oliver Whitaker, David Ormrod Morley, Mark Wilson

引用次数: 0

Molecular structures with spectroscopic accuracy at DFT cost by the templating synthon approach and the PCS141 database. 模板合成方法和PCS141数据库在DFT成本下具有光谱精度的分子结构。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0255564

Federico Lazzari, Silvia Di Grande, Luigi Crisci, Marco Mendolicchio, Vincenzo Barone

{"title":"Molecular structures with spectroscopic accuracy at DFT cost by the templating synthon approach and the PCS141 database.","authors":"Federico Lazzari, Silvia Di Grande, Luigi Crisci, Marco Mendolicchio, Vincenzo Barone","doi":"10.1063/5.0255564","DOIUrl":"https://doi.org/10.1063/5.0255564","url":null,"abstract":"The computation of accurate geometric parameters at density functional theory cost for large molecules in the gas phase is addressed through a novel strategy that combines quantum chemical models with machine learning techniques. The first key step is the expansion of a database of accurate semi-experimental equilibrium structures with additional molecular geometries optimized by version 2 of the Pisa composite scheme. Then, the templating synthon approach is used to improve the accuracy of structures optimized by a hybrid density functional paired with a double zeta basis set, leveraging chemical similarity to cluster different molecular environments and refine bond lengths and valence angles. A set of prototypical biomolecular building blocks is used to demonstrate that it is possible to achieve spectroscopic accuracy for molecular systems too large to be treated by state-of-the-art composite wavefunction methods. In addition, a freely accessible web-based tool has been developed to facilitate the post-processing of geometries optimized using standard electronic structure codes, thereby providing an accurate and efficient tool for the computational study of medium- to large-sized molecules, also accessible to experiment-oriented researchers.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 11","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

How the choice of exchange-correlation functional affects DFT-based simulations of the hydrated electron. 交换相关泛函的选择如何影响基于dft的水合电子模拟。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0253369

William R Borrelli, Xiaoyan Liu, Benjamin J Schwartz

{"title":"How the choice of exchange-correlation functional affects DFT-based simulations of the hydrated electron.","authors":"William R Borrelli, Xiaoyan Liu, Benjamin J Schwartz","doi":"10.1063/5.0253369","DOIUrl":"https://doi.org/10.1063/5.0253369","url":null,"abstract":"Hydrated electrons are anionic species that are formed when an excess electron is introduced into liquid water. Building an understanding of how hydrated electrons behave in solution has been a long-standing effort of simulation methods, of which density functional theory (DFT) has come to the fore in recent years. The ability of DFT to model the reactive chemistry of hydrated electrons is an attractive advantage over semi-classical methodologies; however, relatively few density functional approximations (DFAs) have been used for the hydrated electron simulations presented in the literature. Here, we simulate hydrated electron systems using a series of exchange-correlation (XC) functionals spanning Jacob's ladder. We calculate a variety of experimental and other observables of the hydrated electron and compare the XC functional dependence for each quantity. We find that the formation of a stable localized hydrated electron is not necessarily limited to hybrid XC functionals and that some hybrid functionals produce delocalized hydrated electrons or electrons that react with the surrounding water at an unphysically fast rate. We further characterize how different DFAs impact the solvent structure and predicted spectroscopy of the hydrated electron, considering several methods for calculating the hydrated electron's absorption spectrum for the best comparison between structures generated using different density functionals. None of the dozen or so DFAs that we investigated are able to correctly predict the hydrated electron's spectroscopy, vertical detachment energy, or molar solvation volume.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 11","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143657355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adaptive-precision potentials for large-scale atomistic simulations. 大规模原子模拟的自适应精度势。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0245877

David Immel, Ralf Drautz, Godehard Sutmann

{"title":"Adaptive-precision potentials for large-scale atomistic simulations.","authors":"David Immel, Ralf Drautz, Godehard Sutmann","doi":"10.1063/5.0245877","DOIUrl":"https://doi.org/10.1063/5.0245877","url":null,"abstract":"Large-scale atomistic simulations rely on interatomic potentials, providing an efficient representation of atomic energies and forces. Modern machine-learning (ML) potentials provide the most precise representation compared to electronic structure calculations, while traditional potentials provide a less precise but computationally much faster representation and, thus, allow simulations of larger systems. We present a method to combine a traditional and a ML potential into a multi-resolution description, leading to an adaptive-precision potential with an optimum of performance and precision in large, complex atomistic systems. The required precision is determined per atom by a local structure analysis and updated automatically during simulation. We use copper as demonstrator material with an embedded atom model as classical force field and an atomic cluster expansion (ACE) as ML potential, but, in principle, a broader class of potential combinations can be coupled by this method. The approach is developed for the molecular-dynamics simulator LAMMPS and includes a load-balancer to prevent problems due to the atom dependent force-calculation times, which makes it suitable for large-scale atomistic simulations. The developed adaptive-precision copper potential represents the ACE-forces with a precision of 10 me V/Å and the ACE-energy exactly for the precisely calculated atoms in a nanoindentation of 4 × 106 atoms calculated for 100 ps and shows a speedup of 11.3 compared with a full ACE simulation.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 11","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transition path and interface sampling of stochastic Schrödinger dynamics. 随机薛定谔动力学的过渡路径和界面采样

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0246727

Robson Christie, Peter G Bolhuis, David T Limmer

引用次数: 0

Pareto-based optimization of sparse dynamical systems. 稀疏动力系统的pareto优化。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0249780

Gianmarco Ducci, Maryke Kouyate, Karsten Reuter, Christoph Scheurer

引用次数: 0

Unraveling cation-cation "attraction" in argentophilic interaction in 2,2'-bipydine coordinated silver complex. 揭示2,2'-联吡啶配位银络合物中亲银相互作用中的阳离子-阳离子“吸引力”。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0258704

Yuan Xu

{"title":"Unraveling cation-cation \"attraction\" in argentophilic interaction in 2,2'-bipydine coordinated silver complex.","authors":"Yuan Xu","doi":"10.1063/5.0258704","DOIUrl":"https://doi.org/10.1063/5.0258704","url":null,"abstract":"The nature of argentophilic interaction in the 2,2'-bipyridine-coordinated silver complex, which manifests counterintuitive cation-cation \"attraction,\" is attributed to ligand stacking and solvation effects in the present article. While charged closed-shell transition metal complexes aggregating spontaneously to form oligomers has long been observed experimentally, the interpretation of the nature of so-called metallophilicity is still ongoing. For the dimer [(2,2'-bpy)2Ag]22+, qualitative electrostatic potential, non-covalent interaction, atoms-in-molecules analyses, and quantitative energy decomposition analysis calculations indicate that the electrostatic repulsion between two like formal charges at silver centers can be overcome by long-range dispersion attraction and short-range electronic correlation from ligands. In addition, delocalizing the net charges on silvers over the whole ligands can decrease electrostatic repulsion of metal centers to stabilize oligomers. The vital role of the screening effect of solvent has also been realized in the bound binding of the title system. Overall, this research highlights the importance of ligand stacking to argentophilicity, while d10-d10 attraction of silver centers presents quite little contribution.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 11","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143657453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correlation between entropy fluctuations and the dielectric relaxation of glass-forming systems: The central role of dipolar-dipolar cross correlations. 熵涨落与玻璃形成系统介电弛豫之间的关系：偶极-偶极交叉相关的中心作用。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-03-21 DOI: 10.1063/5.0250974

S Arrese-Igor

{"title":"Correlation between entropy fluctuations and the dielectric relaxation of glass-forming systems: The central role of dipolar-dipolar cross correlations.","authors":"S Arrese-Igor","doi":"10.1063/5.0250974","DOIUrl":"https://doi.org/10.1063/5.0250974","url":null,"abstract":"The premise that the dielectric α relaxation has a one-to-one correspondence with entropy fluctuations in equilibrium near the glass transition was experimentally verified in a systematic and quantitative manner for glass-forming systems in general. Validation of this relation was structured at different levels, taking into account various ingredients as the apolar-polar character, macromolecular structure, the presence of hydrogen bonds, or complex structure and dynamics. The results reclaim the suitability of dielectric spectroscopy to echo the primary structural relaxation of glass-forming systems, demonstrating that the dielectric response effectively captures the structural relaxation by reliably correlating with entropy fluctuations. The correlation with entropy fluctuations holds even when the dielectric strength of the systems is high and the dielectric response is narrow and dominated by cross correlations, proving that dipolar intermolecular interactions are fundamental to the structural relaxation and not a particularity of the dielectric probe. This one-to-one correspondence between structural and dielectric α relaxation does not support the existence of a generic spectral shape for the primary structural relaxation valid for all kinds of susceptibility functions.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 11","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143674054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0