The Journal of Physical Chemistry A最新文献

{"title":"Improvement of Fourteen Coupled Global Potential Energy Surfaces of ³<i>A'</i> States of O + O₂.","authors":"Xiaorui Zhao, Yinan Shu, Qinghui Meng, Jie J Bao, Xuefei Xu, Donald G Truhlar","doi":"10.1021/acs.jpca.5c00464","DOIUrl":"https://doi.org/10.1021/acs.jpca.5c00464","url":null,"abstract":"<p><p>We improved the potential energy surfaces for 14 coupled ³<i>A'</i> states of O₃ by using parametrically managed diabatization by deep neural network (PM-DDNN) with three improvements: (1) We used a new functional form for the parametrically managed activation function, which ensures the continuity of the coordinates used in the parametric management. (2) We used higher weighting for low-lying states to achieve smoother potential energy surfaces. (3) The asymptotic behavior of the coupled potential energy surfaces was further refined by utilizing a better low-dimensional potential. As a result of these improvements, we obtained significantly smoother potentials that are better suited for dynamics calculations. For the new version of 14 coupled ³<i>A'</i> surfaces, the entire set of 532,560 adiabatic energies are fit with a mean unsigned error (MUE) of 45 meV, which is only 0.7% of the mean energy in the data set, which is 6.24 eV.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143661552","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}

{"title":"Unraveling the Geometrical Effects on Singlet Fission of Carotenoids: A Model Perspective.","authors":"Supriyo Santra, Debashree Ghosh","doi":"10.1021/acs.jpca.5c00060","DOIUrl":"10.1021/acs.jpca.5c00060","url":null,"abstract":"<p><p>Singlet fission (SF) is a phenomenon that generates multiple excitons (triplets) on different chromophores from a single exciton (singlet) on one chromophore. Owing to the strong electronic correlation and a complicated excited state manifold of carotenoids (polyenes), the SF mechanism in carotenoids is different from acenes shown in <i>J. Phys. Chem. Lett.</i>, <b>2022</b>, <i>13</i>, 6800-6805. However, the mechanism is expected to have significant effects of the geometry in the excited state and strong vibronic couplings between these low-lying excited states. Employing high-level state-of-the-art electronic structure methods, we show that the dark <i>A</i>_g states and charge transfer components play a major role in the SF process. The success of the process is strongly dependent on the relative orientation of the monomers. We have also shown that the high-frequency modes involving changes in bond length alternation are strongly coupled to the excited electronic states. These nuclear vibrational modes facilitate the SF process.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2738-2744"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555362","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}

{"title":"Kelvin Probe Method to Evaluate Polarization Properties of Liquids.","authors":"Haruto Jibiki, Masato Suzuki, Masahiro Ohara, Hisao Ishii","doi":"10.1021/acs.jpca.4c08604","DOIUrl":"10.1021/acs.jpca.4c08604","url":null,"abstract":"<p><p>The polarization behavior analysis within dielectric materials is crucial for electronics. Here, we reconsidered the Kelvin probe (KP) technique, a widely used method for determining the work function and surface potential of solid materials, for assessing the polarization properties of deformable materials. Unlike impedance spectroscopy (IS), the KP technique measures displacement current by modulating the electrode spacing, rather than electrode potential. By phase-separating KP signal into displacement current and its delayed component (actual current), the KP method is expected to selectively measure polarization properties within the bulk, as the potential drop in the bulk and interface remains constant. We achieved precise phase separation of the KP signal using an optical lever signal synchronized with the electrode vibration as the reference for the lock-in amplifier. The complex dielectric constants ε_r, KP^* and ε_r, IS^* of liquid samples were measured by KP and IS measurement, respectively. For nonpolar octane, ε_r, KP^* was almost equal to ε_r, IS^*. Alternatively, for polar 1-octanol and 2-octanol, ε_r, KP^* was smaller than ε_r, IS^*. We also estimated that the bulk potential drop in 1-octanol and 2-octanol is approximately one-tenth of the total potential drop. The proposed approach offers a novel method for evaluating energy diagrams and provides insights into the polarization mechanisms of deformable materials.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2812-2821"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565513","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}

{"title":"The Source of Some Empirical Density Functionals van der Waals Forces.","authors":"A V Leonov, D U Zaripov, R Yu Dokin, T V Losev, I S Gerasimov, M G Medvedev","doi":"10.1021/acs.jpca.4c07586","DOIUrl":"10.1021/acs.jpca.4c07586","url":null,"abstract":"<p><p>Density functional approximations became indispensable tools in many fields of chemistry due to their excellent cost-to-accuracy ratio. Still, consideration is required to select an appropriate approximation for each task. Highly parameterized Minnesota functionals are known for their excellent accuracy in reproducing thermochemical properties and, in particular, weak medium-range interactions. Here, we show that the latter ability of many Minnesota functionals comes from exploiting the basis set incompleteness. This finding shows how empirical functionals can trick their makers by learning to operate in a physics-defying way and likely explains the previously observed tendency of Minnesota functionals to distort electron densities. Thus, satisfaction of the Hellmann-Feynman theorem should be considered an important test and parameterization goal for the future generations of highly parameterized density functionals, including those based on neural networks.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2806-2811"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571568","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}

{"title":"Correction to \"A Novel Approach for Quantifying Magnetic Susceptibility of Aqueous and Organic Solutions\".","authors":"Konrad Wojtaszek, Andrea Cristofolini, Arturo Popoli, Karolina Kolczyk-Siedlecka, Marek Wojnicki","doi":"10.1021/acs.jpca.5c00949","DOIUrl":"10.1021/acs.jpca.5c00949","url":null,"abstract":"","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2822"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143602978","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}

{"title":"Unusual Tautomerism of Methyl Allophanate: Selective Crystallization of the Minor Component via Hydrogen-Bond Network","authors":"Masashi Hatanaka*,&nbsp;","doi":"10.1021/acs.jpca.4c0837410.1021/acs.jpca.4c08374","DOIUrl":"https://doi.org/10.1021/acs.jpca.4c08374https://doi.org/10.1021/acs.jpca.4c08374","url":null,"abstract":"<p >The unexpected tautomerism of methyl allophanates has been observed in the solid state. X-ray analysis, IR/UV spectroscopic data, and density functional theory (DFT) calculations showed that the molecule adopts an imidic form in the crystal, whereas the amide form, which is more stable in aqueous solution, is expected. The imidic form in the solid state is stabilized by a robust hydrogen-bond network, which facilitates the selective isolation of minor imidic species.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"129 13","pages":"3007–3011 3007–3011"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143758798","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}

{"title":"Systematic Study of Hard-Wall Confinement-Induced Effects on Atomic Electronic Structure.","authors":"Hugo Åström, Susi Lehtola","doi":"10.1021/acs.jpca.4c05641","DOIUrl":"10.1021/acs.jpca.4c05641","url":null,"abstract":"<p><p>We point out that although a litany of studies have been published on atoms in hard-wall confinement, they have either not been systematic, having only looked at select atoms and/or select electron configurations, or they have not used robust numerical methods. To remedy the situation, we perform in this work a methodical study of atoms in hard-wall confinement with the HelFEM program, which employs the finite element method that trivially implements the hard-wall potential, guarantees variational results, and allows for easily finding the numerically exact solution. Our fully numerical calculations are based on nonrelativistic density functional theory and spherically averaged densities. We consider three levels of density functional approximations: the local density approximation employing the Perdew-Wang (PW92) functional, the generalized-gradient approximation (GGA) employing the Perdew-Burke-Ernzerhof (PBE) functional, and the <i>meta</i>-GGA approximation employing the r²SCAN functional. Importantly, the completely dissimilar density functional approximations are in excellent agreement, suggesting that the observed results are not artifacts of the employed level of theory. We systematically examine low-lying configurations of the H-Xe atoms and their monocations and investigate how the configurations─especially the ground-state configuration─behave as a function of the position of the hard-wall boundary. We perform calculations with both spin-polarized as well as spin-restricted densities and demonstrate that spin-polarization effects are significant in open-shell configurations, even though some previous studies have only considered the spin-restricted model. We demonstrate the importance of considering ground-state changes for confined atoms by computing the ionization radii for the H-Xe atoms and observe significant differences to earlier studies. Confirming previous observations, we identify electron shifts on the outermost shells for a majority of the elements: valence s electrons are highly unfavored under strong confinement, and the high-lying 3d and 4f orbitals become occupied in atoms of periods 2-3 and 3-4, respectively. We also comment on deficiencies of a commonly used density-based estimate for the van der Waals (vdW) radius of atoms and propose a better behaved variant in terms of the number of electrons outside the vdW radius that we expect will prove useful in future studies.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2791-2805"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11931545/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143057499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Class of Promising Merocyanine-Functionalized Cd₃₃Se₃₃ Quantum Dots with Strong Fluorescence Emission in Tetrahydrofuran and Acetonitrile.","authors":"Yingxing Li, Chuanfang Zhao, Jinliang Ning, Haiming Duan, Xincun Dou","doi":"10.1021/acs.jpca.5c00378","DOIUrl":"10.1021/acs.jpca.5c00378","url":null,"abstract":"<p><p>Owing to the existence of surface defects, quantum dots (QDs) could be unstable, and thus, the design of proper ligands to improve their stability and optical performance is challenging. In this work, four D-π-<i>A</i> ligands were designed by modulating the D part of merocyanine and were grafted onto Cd₃₃Se₃₃ QD via a Cd-S bond, forming Cd₃₃Se₃₃@D-π-<i>A</i> complexes. It was found that a hole trap appeared between the HOMO and LUMO of the Cd₃₃Se₃₃@D-π-<i>A</i> complexes in vacuum, and the stronger the electron-donating capability of the D part, the higher the activation energy of the trap, which disappeared in solvent environments. The ligand-to-metal charge transfer (LMCT) mechanism of Cd₃₃Se₃₃@D-π-<i>A</i> complexes induced a fluorescence quenching phenomenon in vacuum, while in solution, the local excitation on the D-π-<i>A</i> ligand facilitated stronger fluorescence due to the enhanced electron-donating capability of its D part. The present study provides a strategy for improving the optical performance of functional QDs through the design and optimization of D-π-<i>A</i> ligands, shedding light on the development and applications of novel functional QDs.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2745-2753"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143582141","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}

{"title":"Evaluation of Infrared Intensities Using Diffusion Monte Carlo.","authors":"Pattarapon Moonkaen, Anne B McCoy","doi":"10.1021/acs.jpca.4c08576","DOIUrl":"10.1021/acs.jpca.4c08576","url":null,"abstract":"<p><p>Approaches for evaluating excited state wave functions and energies using diffusion Monte Carlo (DMC) with guiding functions (guided DMC) are discussed. For this work, the guiding functions are functions of a subset of the 3<i>N</i> - 6 coordinates that are needed to describe the structure of the molecule of interest. The DMC wave functions are used to evaluate intensities using two approaches. In the trial wave function approach, the product of the molecular wave function for one of the states involved in the transition and the guiding function for the second state is used to evaluate the matrix elements of the dipole moment. In the descendant weighting approach, descendant weights are used to evaluate the value of the wave function for one of the states involved in the transition at the geometries sampled by the DMC wave function for the second state. The descendant weighting approximation is shown to be more accurate as well as computationally more expensive compared to approximations that are based on various forms of the trial wave function approach. Strategies are explored, which combine results of different forms of the trial wave function approximation to minimize the errors in this approach. The trial wave function and descendant weighting approaches are applied to a study of a harmonic oscillator, where the sensitivity of the calculated energies and intensities to the quality of the trial wave function is explored. The two approaches are also applied to calculations of frequencies and intensities of transitions in water, H₃O₂^-, a four-dimensional (4D) model based on H₃O₂^- and H₅O₂⁺. We also show how comparisons of the results obtained using several forms of the trial wave function approach allow us to explore how couplings among vibrational motions are reflected in the intensities.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2705-2717"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571566","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}

{"title":"Modeling Pb(II) Adsorption on Mineral Surfaces: Bridging Density Functional Theory and Experiment with Thermodynamic Insights.","authors":"Jennifer L Bjorklund, Logan J Augustine, Ali Abbaspour Tamijani, Thomas P Trainor, Anne M Chaka, Sara E Mason","doi":"10.1021/acs.jpca.5c00390","DOIUrl":"10.1021/acs.jpca.5c00390","url":null,"abstract":"<p><p>Despite decades of work on aqueous lead (Pb) adsorption on α-Fe₂O₃ (hematite) and α-Al₂O₃ (alumina), gaps between measurements and modeling obscure molecular-level understanding. Achieving well-matched geometries between theory and experiment for mineral-water interfaces is a hurdle, as surface functional group type and distribution must be accounted for in determining mechanisms. Additionally, computational methods that can describe the substrate are often not appropriate to capture aqueous effects. Progress requires focusing on well-studied and relevant systems, such as key facets (001), (012), and (110) of hematite and alumina, and ubiquitous contaminants such as aqueous Pb. In the past, bulk-parameterized bond-valence principles were used to rationalize Pb(II) adsorption trends. These approaches can break down at surfaces, where flexible bonding environments and adsorption-induced surface relaxations play a critical role. Here, we adapt and apply a density functional theory (DFT) and thermodynamics framework, integrating DFT-calculated energies with experimental data and electrochemical principles, to predict Pb(II) adsorption. Our model results capture trends across the full set of surfaces and predict that inner-sphere Pb(II) sorption on (001) alumina varies from unfavorable to weakly favorable across a range of pH conditions. This aligns with experimental insights that Pb(II) interacts at that surface through outer-sphere interactions. Extending to Fe(II) adsorption, we demonstrate a coverage-dependent site preference, potentially explaining disorder in overlayers grown by the oxidative adsorption of Fe(II) on hematite (001).</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"2754-2767"},"PeriodicalIF":2.7,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571567","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}