The Journal of Chemical Physics最新文献_第7页

A population balance model for the kinetics of covalent organic framework synthesis. 共价有机框架合成动力学的种群平衡模型。

The Journal of Chemical Physics Pub Date : 2024-04-28 DOI: 10.1063/5.0197656

Howard Weatherspoon, Baron Peters

引用次数: 0

ExROPPP: Fast, accurate, and spin-pure calculation of the electronically excited states of organic hydrocarbon radicals ExROPPP：快速、准确、自旋纯计算有机碳氢化合物自由基的电子激发态

The Journal of Chemical Physics Pub Date : 2024-04-26 DOI: 10.1063/5.0191373

James D. Green, Timothy J. H. Hele

{"title":"ExROPPP: Fast, accurate, and spin-pure calculation of the electronically excited states of organic hydrocarbon radicals","authors":"James D. Green, Timothy J. H. Hele","doi":"10.1063/5.0191373","DOIUrl":"https://doi.org/10.1063/5.0191373","url":null,"abstract":"Recent years have seen an explosion of interest in organic radicals due to their promise for highly efficient organic light-emitting diodes and molecular qubits. However, accurately and inexpensively computing their electronic structure has been challenging, especially for excited states, due to the spin-contamination problem. Furthermore, while alternacy or “pseudoparity” rules have guided the interpretation and prediction of the excited states of closed-shell hydrocarbons since the 1950s, similar general rules for hydrocarbon radicals have not to our knowledge been found yet. In this article, we present solutions to both of these challenges. First, we combine the extended configuration interaction singles method with Pariser–Parr–Pople (PPP) theory to obtain a method that we call ExROPPP (Extended Restricted Open-shell PPP) theory. We find that ExROPPP computes spin-pure excited states of hydrocarbon radicals with comparable accuracy to experiment as high-level general multi-configurational quasi-degenerate perturbation theory calculations but at a computational cost that is at least two orders of magnitude lower. We then use ExROPPP to derive widely applicable rules for the spectra of alternant hydrocarbon radicals, which are completely consistent with our computed results. These findings pave the way for highly accurate and efficient computation and prediction of the excited states of organic radicals.","PeriodicalId":501648,"journal":{"name":"The Journal of Chemical Physics","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140799727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

VAMPyR—A high-level Python library for mathematical operations in a multiwavelet representation VAMPyR - 用于多小波表示数学运算的高级 Python 库

The Journal of Chemical Physics Pub Date : 2024-04-26 DOI: 10.1063/5.0203401

Magnar Bjørgve, Christian Tantardini, Stig Rune Jensen, Gabriel A. Gerez S., Peter Wind, Roberto Di Remigio Eikås, Evgueni Dinvay, Luca Frediani

{"title":"VAMPyR—A high-level Python library for mathematical operations in a multiwavelet representation","authors":"Magnar Bjørgve, Christian Tantardini, Stig Rune Jensen, Gabriel A. Gerez S., Peter Wind, Roberto Di Remigio Eikås, Evgueni Dinvay, Luca Frediani","doi":"10.1063/5.0203401","DOIUrl":"https://doi.org/10.1063/5.0203401","url":null,"abstract":"Wavelets and multiwavelets have lately been adopted in quantum chemistry to overcome challenges presented by the two main families of basis sets: Gaussian atomic orbitals and plane waves. In addition to their numerical advantages (high precision, locality, fast algorithms for operator application, linear scaling with respect to system size, to mention a few), they provide a framework that narrows the gap between the theoretical formalism of the fundamental equations and the practical implementation in a working code. This realization led us to the development of the Python library called VAMPyR (Very Accurate Multiresolution Python Routines). VAMPyR encodes the binding to a C++ library for multiwavelet calculations (algebra and integral and differential operator application) and exposes the required functionality to write a simple Python code to solve, among others, the Hartree–Fock equations, the generalized Poisson equation, the Dirac equation, and the time-dependent Schrödinger equation up to any predefined precision. In this study, we will outline the main features of multiresolution analysis using multiwavelets and we will describe the design of the code. A few illustrative examples will show the code capabilities and its interoperability with other software platforms.","PeriodicalId":501648,"journal":{"name":"The Journal of Chemical Physics","volume":"229 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140799609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ab initio path integral Monte Carlo simulations of warm dense two-component systems without fixed nodes: Structural properties 无固定节点的温暖致密双组分系统的 Ab initio 路径积分蒙特卡罗模拟：结构特性

The Journal of Chemical Physics Pub Date : 2024-04-26 DOI: 10.1063/5.0206787

Tobias Dornheim, Sebastian Schwalbe, Maximilian P. Böhme, Zhandos A. Moldabekov, Jan Vorberger, Panagiotis Tolias

引用次数: 0

Unmasking quantum effects in the surface thermodynamics of fluid nanodrops. 揭示流体纳米滴表面热力学中的量子效应。

The Journal of Chemical Physics Pub Date : 2024-04-25 DOI: 10.1063/5.0196501

Sergio Contreras, A. Martínez-Borquez, Carlos Avendaño, A. Gil-Villegas, George Jackson

{"title":"Unmasking quantum effects in the surface thermodynamics of fluid nanodrops.","authors":"Sergio Contreras, A. Martínez-Borquez, Carlos Avendaño, A. Gil-Villegas, George Jackson","doi":"10.1063/5.0196501","DOIUrl":"https://doi.org/10.1063/5.0196501","url":null,"abstract":"The focus of our study is an in-depth investigation of the quantum effects associated with the surface tension and other thermodynamic properties of nanoscopic liquid drops. The behavior of drops of quantum Lennard-Jones fluids is investigated with path-integral Monte Carlo simulations, and the test-area method is used to determine the surface tension of the spherical vapor-liquid interface. As the thermal de Broglie wavelength, λB, becomes more significant, the average density of the liquid drop decreases, with the drop becoming mechanically unstable at large wavelengths. As a consequence, the surface tension is found to decrease monotonically with λB, vanishing altogether for dominant quantum interactions. Quantum effects can be significant, leading to values that are notably lower than the classical thermodynamic limit, particularly for smaller drops. For planar interfaces (with infinite periodicity in the direction parallel to the interface), quantum effects are much less significant with the same values of λB but are, nevertheless, consequential for values representative of hydrogen or helium-4 at low temperatures corresponding to vapor-liquid coexistence. Large quantum effects are found for small drops of molecules with quantum interactions corresponding to water, ethane, methanol, and carbon dioxide, even at ambient conditions. The notable decrease in the density and tension has important consequences in reducing the Gibbs free-energy barrier of a nucleating cluster, enhancing the nucleation kinetics of liquid drops and of bubble formation. This implies that drops would form at a much greater rate than is predicted by classical nucleation theory.","PeriodicalId":501648,"journal":{"name":"The Journal of Chemical Physics","volume":"10 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140658867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultrafast electron diffraction of photoexcited gas-phase cyclobutanone predicted by ab initio multiple cloning simulations 通过ab initio多重克隆模拟预测光激发气相环丁酮的超快电子衍射

The Journal of Chemical Physics Pub Date : 2024-04-25 DOI: 10.1063/5.0203683

Dmitry V. Makhov, Lewis Hutton, Adam Kirrander, Dmitrii V. Shalashilin

引用次数: 0

Rotational spectrum, structure, and quadrupole coupling of cyclopropylchloromethyldifluorosilane. 环丙基氯甲基二氟硅烷的旋转光谱、结构和四极耦合。

The Journal of Chemical Physics Pub Date : 2024-04-25 DOI: 10.1063/5.0203016

Alexander R Davies, Abanob G Hanna, Alma Lutas, G. Guirgis, G. S. Grubbs

{"title":"Rotational spectrum, structure, and quadrupole coupling of cyclopropylchloromethyldifluorosilane.","authors":"Alexander R Davies, Abanob G Hanna, Alma Lutas, G. Guirgis, G. S. Grubbs","doi":"10.1063/5.0203016","DOIUrl":"https://doi.org/10.1063/5.0203016","url":null,"abstract":"Cyclopropylchloromethyldifluorosilane, c-C3H5SiF2CH2Cl, has been synthesized, and its rotational spectrum has been recorded by chirped-pulse Fourier transform microwave spectroscopy. The spectral analysis of several isotopologues indicates the presence of two distinct conformations in the free-jet expansion, which are interconvertible through a rotation of the chloromethyl group. A partial substitution structure is presented for the lower energy conformation and is compared to the equilibrium structure obtained from quantum chemical calculations. Additionally, the presence of the chlorine nucleus leads to the rotational transitions splitting into multiple hyperfine components and χaa, a measure of the electric field gradient along the a axis, is unusually small at merely +0.1393(73) MHz. Various common ab initio and density functional theory methods fail to predict good quadrupole coupling constants (in the principal axis system) that adequately reproduce the observed hyperfine splitting, although diagonalizing the quadrupole coupling tensor from the principal axis system into a nucleus-centered axis system reveals that, overall, these methods calculate reasonably the electric field gradient about the chlorine nucleus. Finally, a total of nine electric dipole forbidden, quadrupole allowed transitions are observed in the rotational spectra of the parent species of the higher energy conformation and the 37Cl isotopologue of the lower energy conformation. These include those of x-type (no change in parity of Ka or Kc), which, to our knowledge, is the first time such transitions have been observed in a chlorine-containing molecule.","PeriodicalId":501648,"journal":{"name":"The Journal of Chemical Physics","volume":"8 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140653490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optical spin hall effect in exciton-polariton condensates in lead halide perovskite microcavities. 卤化铅过氧化物微腔中激子-极化子凝聚态的光自旋霍尔效应。

The Journal of Chemical Physics Pub Date : 2024-04-25 DOI: 10.1063/5.0202341

Bo Xiang, Yi-Lin Li, M. S. Spencer, Yanan Dai, Yusong Bai, D. Basov, X-Y Zhu

{"title":"Optical spin hall effect in exciton-polariton condensates in lead halide perovskite microcavities.","authors":"Bo Xiang, Yi-Lin Li, M. S. Spencer, Yanan Dai, Yusong Bai, D. Basov, X-Y Zhu","doi":"10.1063/5.0202341","DOIUrl":"https://doi.org/10.1063/5.0202341","url":null,"abstract":"An exciton-polariton condensate is a hybrid light-matter state in the quantum fluid phase. The photonic component endows it with characters of spin, as represented by circular polarization. Spin-polarization can form stochastically for quasi-equilibrium exciton-polariton condensates at parallel momentum vector k|| ∼ 0 from bifurcation or deterministically for propagating condensates at k|| > 0 from the optical spin-Hall effect (OSHE). Here, we report deterministic spin-polarization in exciton-polariton condensates at k|| ∼ 0 in microcavities containing methylammonium lead bromide perovskite (CH3NH3PbBr3) single crystals under non-resonant and linearly polarized excitation. We observe two energetically split condensates with opposite circular polarizations and attribute this observation to the presence of strong birefringence, which introduces a large OSHE at k|| ∼ 0 and pins the condensates in a particular spin state. Such spin-polarized exciton-polariton condensates may serve not only as circularly polarized laser sources but also as effective alternatives to ultracold atom Bose-Einstein condensates in quantum simulators of many-body spin-orbit coupling processes.","PeriodicalId":501648,"journal":{"name":"The Journal of Chemical Physics","volume":"19 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140653957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Photoionization cross sections measurements of the excited states of lutetium and ytterbium in the near threshold region. 近阈值区镥和镱激发态的光电离截面测量。

The Journal of Chemical Physics Pub Date : 2024-04-25 DOI: 10.1063/5.0197941

Zhenmei Zhang, Zhicheng Wang, Qiaolin Wang, Xiaokang Ma, Zhixie Wang, Zefeng Hua, Guanxin Yao, Xinyan Yang, Zhongfa Sun, Zhengbo Qin, Xianfeng Zheng

引用次数: 0

Formation of a two-dimensional helical square tube ice in hydrophobic nanoslit using the TIP5P water model. 利用 TIP5P 水模型在疏水纳米光中形成二维螺旋方管冰。

The Journal of Chemical Physics Pub Date : 2024-04-25 DOI: 10.1063/5.0205343

Jiaxian Li, Chongqin Zhu, Wenhui Zhao, Yurui Gao, Jaeil Bai, Jian Jiang, X. Zeng

{"title":"Formation of a two-dimensional helical square tube ice in hydrophobic nanoslit using the TIP5P water model.","authors":"Jiaxian Li, Chongqin Zhu, Wenhui Zhao, Yurui Gao, Jaeil Bai, Jian Jiang, X. Zeng","doi":"10.1063/5.0205343","DOIUrl":"https://doi.org/10.1063/5.0205343","url":null,"abstract":"In extreme and nanoconfinement conditions, the tetrahedral arrangement of water molecules is challenged, resulting in a rich and new phase behavior unseen in bulk phases. The unique phase behavior of water confined in hydrophobic nanoslits has been previously observed, such as the formation of a variety of two-dimensional (2D) ices below the freezing temperature. The primary identified 2D ice phase, termed square tube ice (STI), represents a unique arrangement of water molecules in 2D ice, which can be viewed as an array of 1D ice nanotubes stacked in the direction parallel to the confinement plane. In this study, we report the molecular dynamics (MD) simulations evidence of a novel 2D ice phase, namely, helical square tube ice (H-STI). H-STI is characterized by the stacking of helical ice nanotubes in the direction parallel to the confinement plane. Its structural specificity is evident in the presence of helical square ice nanotubes, a configuration unseen in both STI and single-walled ice nanotubes. A detailed analysis of the hydrogen bonding strength showed that H-STI is a 2D ice phase diverging from the Bernal-Fowler-Pauling ice rules by forming only two strong hydrogen bonds between adjacent molecules along its helical ice chain. This arrangement of strong hydrogen bonds along ice nanotube and weak bonds between the ice nanotube shows a similarity to quasi-one-dimensional van der Waals materials. Ab initio molecular dynamics simulations (over a 30 ps) were employed to further verify H-STI's stability at 1 GPa and temperature up to 200 K.","PeriodicalId":501648,"journal":{"name":"The Journal of Chemical Physics","volume":"5 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140653867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0