Journal of Chemical Physics最新文献

Dynamical heterogeneity in supercooled water and its spectroscopic fingerprints. 过冷水的动力学非均质性及其光谱指纹图谱。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0288343

Cesare Malosso, Edward Danquah Donkor, Stefano Baroni, Ali Hassanali

{"title":"Dynamical heterogeneity in supercooled water and its spectroscopic fingerprints.","authors":"Cesare Malosso, Edward Danquah Donkor, Stefano Baroni, Ali Hassanali","doi":"10.1063/5.0288343","DOIUrl":"https://doi.org/10.1063/5.0288343","url":null,"abstract":"A growing body of theoretical and experimental evidence strongly supports the existence of a second liquid-liquid critical point (LLCP) in deeply supercooled water leading to the co-existence of two phases: a high- and low-density liquid (HDL and LDL). While the thermodynamics associated with this putative LLCP has been well characterized through numerical simulations, the dynamical properties of these two phases close to the critical point remain much less understood. In this work, we investigate their dynamical and spectroscopic features using machine-learning interatomic potentials. Dynamical analyses using the van Hove correlation function reveal that LDL exhibits very sluggish and heterogeneous molecular mobility, in contrast to the faster and more homogeneous dynamics of HDL. Infrared absorption (IR) spectra further show clear vibrational distinctions between LDL and HDL, in particular in the far IR region between 400 and 1000 cm-1. Together, these findings provide new dynamical fingerprints that clarify the microscopic behavior of supercooled water and offer valuable guidance for experimental efforts aimed at detecting the long-sought liquid-liquid transition.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 14","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145274743","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

Time-resolved solvation of alkali ions in superfluid helium nanodroplets: Theoretical simulation of a pump-probe study. 超流氦纳米液滴中碱离子的时间分辨溶剂化：泵-探针研究的理论模拟。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0291643

Ernesto García-Alfonso, Manuel Barranco, Martí Pi, Nadine Halberstadt

{"title":"Time-resolved solvation of alkali ions in superfluid helium nanodroplets: Theoretical simulation of a pump-probe study.","authors":"Ernesto García-Alfonso, Manuel Barranco, Martí Pi, Nadine Halberstadt","doi":"10.1063/5.0291643","DOIUrl":"https://doi.org/10.1063/5.0291643","url":null,"abstract":"The solvation process of an alkali ion (Na+, K+, Rb+, and Cs+) inside a superfluid 4He2000 nanodroplet is investigated theoretically using liquid 4He time-dependent density functional theory at zero temperature. We simulate both steps of the pump-probe experiment conducted on Na+ [Albrechtsen et al., Nature 623, 319 (2023)], where the alkali atom residing at the droplet surface is ionized by the pump pulse and its solvation is probed by ionizing a central xenon atom and detecting the expulsed Na+Hen ions. Our results confirm the Poissonian model for the binding of the first five He atoms for the lighter Na+ and K+ alkalis, with a rate in good agreement with the more recent experimental results on Na+ [Albrechtsen et al., J. Chem. Phys. 162, 174309 (2025)]. For the probe step, we show that the ion takes several picoseconds to get out of the droplet. During this rather long time, the solvation structure around it is very hot and far from equilibrium, and it can gain or lose more He atoms. Surprisingly, analyzing the Na+ solvation structure energy reveals that it is not stable by itself during the first few picoseconds of the solvation process. After that, energy relaxation follows a Newton behavior, as found experimentally, but with a longer time delay, 5.0 ≤ t0 ≤ 6.5 ps vs 0.23 ± 0.06 ps, and characteristic time, 7.3 ≤ τ ≤ 16.5 ps vs 2.6 ± 0.4 ps. We conclude that the first instants of the solvation process are highly turbulent and that the solvation structure is stabilized only by the surrounding helium \"solvent.\"","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 14","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145274770","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

A theory for diffusion-controlled reactions within nonequilibrium steady states. 非平衡稳定状态下扩散控制反应的理论。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0284657

Seokjin Moon, David T Limmer

引用次数: 0

Nonadiabatic photodissociation dynamics of indole using multi-configuration time-dependent Hartree method. 吲哚非绝热光解动力学的多构型时变Hartree方法。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0287684

Soumyadip Ray, Sudip Sasmal, Padmabati Mondal

{"title":"Nonadiabatic photodissociation dynamics of indole using multi-configuration time-dependent Hartree method.","authors":"Soumyadip Ray, Sudip Sasmal, Padmabati Mondal","doi":"10.1063/5.0287684","DOIUrl":"https://doi.org/10.1063/5.0287684","url":null,"abstract":"Indole, being a biologically relevant and abundant chromophore, is a prime molecule of interest in both experimental and computational research. In the current work, the N-H photodissociation dynamics of indole have been studied using nonadiabatic quantum dynamics. Potential energy cuts (PECs) along important vibrational modes have been calculated using the multi-state complete active space self-consistent field method with (10,9) active space. The important vibrational modes for the whole process were detected based on symmetry analysis and the strength of the vibronic couplings. The multi-mode multi-state model vibronic Hamiltonian is constructed by the parameters obtained from the fitting of ab initio PECs, including Morse and harmonic functions and vibronic couplings. The nonadiabatic quantum dynamics is performed using a four state multimode Hamiltonian with the multi-configuration time-dependent Hartree method. For the N-H stretching, Q42 turns out to be the most important among all normal modes. The third excited diabatic state shows an anharmonic, dissociative π-σ* character along Q42. The non-adiabatic coupling strength between the La and π-σ* plays a crucial role in controlling the photodissociation. The out-of-plane C-N-H bending, despite being directly related to the N-H group, is found to have a negligible contribution to the photodissociation process. Two timescales obtained from the population dynamics, 26 and 113 fs, are attributed to internal conversion from the second excited La state to the π-σ* states and photodissociation at the π-σ*, respectively, and are in good agreement with timescales obtained from previous experimental studies. Around 80% reaction probability for N-H fission of indole is recorded after 200 fs. This study of photofission of indole is crucial for understanding the photodynamics of similar large molecules.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 14","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145280405","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

A numerically exact calculation of vibration-rotation-tunneling levels of water dimer on a new accurate potential energy surface: Achieving sub-cm-1 accuracy from the terahertz to the infrared. 一种新的精确势能表面上水二聚体振动-旋转-隧道水平的精确数值计算：实现从太赫兹到红外的亚cm-1精度。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0294206

Xiao-Gang Wang, Shuo Yang, Tucker Carrington, Dong H Zhang

{"title":"A numerically exact calculation of vibration-rotation-tunneling levels of water dimer on a new accurate potential energy surface: Achieving sub-cm-1 accuracy from the terahertz to the infrared.","authors":"Xiao-Gang Wang, Shuo Yang, Tucker Carrington, Dong H Zhang","doi":"10.1063/5.0294206","DOIUrl":"https://doi.org/10.1063/5.0294206","url":null,"abstract":"Numerically exact vibrational-rotational-tunneling (VRT) levels of (H2O)2 and (D2O)2 have been computed in full dimensionality on a new highly accurate two-body potential energy surface (PES). Inter-molecular levels are computed with a basis of products of contracted intra-molecular basis functions and inter-molecular functions that are products of Wigner functions. Intra-molecular levels are computed with a product of contracted intra-molecular basis functions and contracted inter-molecular basis functions. We use a two-body PES that is fitted using the fundamental-invariant neural network method using 740 000 ab initio points. Energies for points near the bottom of the well are computed without the frozen-core approximation. The PES has a root-mean-square fitting error of only 0.70 cm-1. All the experimental VRT fork origins and tunneling splittings in the terahertz region (up to 150 cm-1) are in excellent agreement with our calculated levels. The largest error is 0.44 cm-1 for (H2O)2 and 0.85 cm-1 for (D2O)2. The calculated levels also agree very well with the 22, of a possible 24, observed OD stretch vibration-tunneling levels of (D2O)2 [Barclay et al., J. Chem. Phys. 150, 164307 (2019) and Barclay et al., 160, 114314 (2024)], with the largest error being 0.35 cm-1. Coupling, which causes predissociation, makes OH stretch states of (H2O)2 difficult to observe and their assignment is controversial. Our calculations resolve the controversy. For the only rotationally resolved experimental OH stretch state, the as[A] \"2s\" state [Huang and Miller, J. Chem. Phys 91, 6613 (1989)], near 3738 cm-1, the 3 observed vibrational-tunneling levels agree with the calculated levels to within 0.35 cm-1.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 14","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145274660","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

On the choice of acceleration amplitude for predicting shear viscosity using the periodic perturbation method. 周期摄动法预测剪切粘度时加速度幅值的选择。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0292399

Lingfeng Gui, Evangelos Tsochantaris, Kieran Nehil-Puleo, Peter T Cummings, Clare MᶜCabe

{"title":"On the choice of acceleration amplitude for predicting shear viscosity using the periodic perturbation method.","authors":"Lingfeng Gui, Evangelos Tsochantaris, Kieran Nehil-Puleo, Peter T Cummings, Clare MᶜCabe","doi":"10.1063/5.0292399","DOIUrl":"https://doi.org/10.1063/5.0292399","url":null,"abstract":"Shear viscosity is a crucial property for optimizing industrial processes. While data are available for common fluids under ambient conditions, viscosity often needs to be estimated at different temperatures and pressures or for systems lacking experimental measurements. Compared to empirical correlations, molecular simulation offers a molecular-level approach to determine viscosity that not only provides accurate viscosity estimates but also yields insight into the underlying molecular mechanisms and can be readily extended to mixtures. Of the available simulation approaches, the non-equilibrium molecular dynamics periodic perturbation method (PPM) has demonstrated both computational efficiency and accuracy in viscosity prediction. However, implementing PPM requires significant trial and error when selecting acceleration amplitude in order to accurately determine the zero-perturbation viscosity, which increases computational demands and reduces the appeal of the method. In this work, we demonstrate that Quentrec's local order theory provides a superior fit for the dependence of viscosity on acceleration amplitude, enabling accurate extrapolation to zero-perturbation viscosity. The method is applied to a diverse set of 144 organic solvents and yields results that show good agreement with both experimental data and equilibrium molecular dynamics simulations. We further show that data-driven models can accurately estimate the acceleration amplitude corresponding to a given relative deviation from zero-perturbation viscosity. By specifying a reasonable deviation, the estimated acceleration amplitude exhibits lower statistical noise while simultaneously enabling precise reproduction of the computed zero-perturbation viscosity after compensating for the deviation. This approach circumvents the need for sampling multiple acceleration amplitudes and thereby facilitates the implementation of the PPM method.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 14","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145274765","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

An extremely efficient algorithm for (2,2) dynamically weighted constrained complete active space calculations. （2,2）动态加权约束完全活动空间计算的一种高效算法。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0293355

Junhan Chen, Xinchun Wu, Yihan Shao, Joseph Subotnik, Tian Qiu

引用次数: 0

Quenching of long-wavelength non-equilibrium temperature fluctuations in a thermophilic colloidal suspension heated from below. 从下面加热的嗜热胶体悬浮液中长波长非平衡温度波动的猝灭。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0293787

Stefano Castellini, Alberto Vailati

引用次数: 0

Relativistic quintuple-zeta basis sets for the s block. s块的相对论五倍基集。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0297009

Marten L Reitsma, Eifion H Prinsen, Johan D Polet, Anastasia Borschevsky, Kenneth G Dyall

{"title":"Relativistic quintuple-zeta basis sets for the s block.","authors":"Marten L Reitsma, Eifion H Prinsen, Johan D Polet, Anastasia Borschevsky, Kenneth G Dyall","doi":"10.1063/5.0297009","DOIUrl":"https://doi.org/10.1063/5.0297009","url":null,"abstract":"Relativistic basis sets of quintuple-zeta quality are presented for the s-block elements. The basis sets include self-consistent field exponents for the occupied spinors and for the np shell (the latter is considered here a valence orbital). Valence and core correlating functions were optimized within multireference singles and doubles configuration interaction calculations for the ground valence configuration. Diffuse functions optimized for the corresponding anions or derived from neighboring elements are also provided. The new basis sets were applied to a range of basic atomic and molecular properties for benchmarking purposes. Smooth convergence to the basis set limit is observed with increased basis set quality from existing double-zeta, triple-zeta, and quadruple-zeta to the newly developed quintuple-zeta basis sets. The use of these basis sets, in combination with state-of-the-art approaches for the treatment of relativity and correlation, will allow achieving higher accuracy and lower uncertainty than previously possible in calculations on heavy atoms and molecules. The basis sets are available at https://doi.org/10.5281/zenodo.17088050.","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 14","pages":""},"PeriodicalIF":3.1,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145274730","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

Fast enantioconversion of chiral mixtures based on effective two-level models. 基于有效二能级模型的手性混合物的快速对映体转化。

IF 3.1 2区化学

Journal of Chemical Physics Pub Date : 2025-10-14 DOI: 10.1063/5.0284446

Jian-Jian Cheng, Yao Du, Xi Yang Zhao, JunLing Che

引用次数: 0