The Journal of Physical Chemistry A最新文献

{"title":"Anisotropic Shock Response of 3,4-Dinitropyrazole Revealed by First-Principles Calculations.","authors":"Chaowen Yang, Yi Yang, Shuangfei Zhu, Shuhai Zhang, Yang Liu, Yahong Chen","doi":"10.1021/acs.jpca.4c06583","DOIUrl":"10.1021/acs.jpca.4c06583","url":null,"abstract":"<p><p>DNP (3,4-dinitropyrazole) has attracted much interest due to its promising melting characteristics and high detonation performances, such as low melting point, high density, high detonation velocity, and low sensitivity. In this work, first-principles molecular dynamics (MD) simulations were performed to investigate the anisotropic shock response of DNP in conjunction with the multiscale shock technique (MSST). The initial decomposition mechanism was revealed through the evolution of the chemical reaction and product analysis. Independent gradients based on the Hirshfeld partition (IGMH) method showed that van der Waals forces mainly exist between the layered structures. Chemical reaction analyses revealed four major initial decomposition reactions for the DNP molecule. At different shock velocities, the molecules in <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>01</mn><mo>)</mo></math> were more inclined to undergo H dissociation reactions, whereas the molecules in <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>0</mn><mover><mn>1</mn><mo>¯</mo></mover><mo>)</mo></math> were more inclined to undergo nitro-dissociation reactions. Product analysis showed that the faster the shock velocities, the earlier the DNP molecules completely disappeared. Furthermore, N₂ and CO₂ were mainly produced by the ring-opening reaction, and their numbers in <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>01</mn><mo>)</mo></math> were higher than in <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>0</mn><mover><mn>1</mn><mo>¯</mo></mover><mo>)</mo></math>, indicating that the ring-opening reaction was more easy to occur in <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>01</mn><mo>)</mo></math>. The ring-opening reaction mainly occurred in <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>01</mn><mo>)</mo></math>, suggesting that <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>01</mn><mo>)</mo></math> was more decomposable than <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>0</mn><mover><mn>1</mn><mo>¯</mo></mover><mo>)</mo></math>. The fitting results of the state equation showed that the theoretical detonation pressures for <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>01</mn><mo>)</mo></math> and <math><mo>(</mo><mover><mn>1</mn><mo>¯</mo></mover><mn>0</mn><mover><mn>1</mn><mo>¯</mo></mover><mo>)</mo></math> are close to the experimental value. These results could help to increase the understanding of shock-induced anisotropy in energetic materials.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"695-704"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142976749","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":"Accelerating Fock Build via Hybrid Analytical-Numerical Integration.","authors":"Yong Zhang, Rongding Lei, Bingbing Suo, Wenjian Liu","doi":"10.1021/acs.jpca.4c07454","DOIUrl":"https://doi.org/10.1021/acs.jpca.4c07454","url":null,"abstract":"&lt;p&gt;&lt;p&gt;A hybrid analytical-numerical integration scheme is introduced to accelerate the Fock build in self-consistent field (SCF) and time-dependent density functional theory (TDDFT) calculations. To evaluate the Coulomb matrix &lt;b&gt;J&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;], the density matrix &lt;b&gt;D&lt;/b&gt; is first decomposed into two parts, the superposition of atomic density matrices &lt;b&gt;D&lt;/b&gt;&lt;sub&gt;⊕&lt;/sub&gt;&lt;sup&gt;&lt;i&gt;A&lt;/i&gt;&lt;/sup&gt; and the rest &lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;R&lt;/i&gt;&lt;/sup&gt; = &lt;b&gt;D&lt;/b&gt;-&lt;b&gt;D&lt;/b&gt;&lt;sub&gt;⊕&lt;/sub&gt;&lt;sup&gt;&lt;i&gt;A&lt;/i&gt;&lt;/sup&gt;. While &lt;b&gt;J&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sub&gt;⊕&lt;/sub&gt;&lt;sup&gt;&lt;i&gt;A&lt;/i&gt;&lt;/sup&gt;] is evaluated analytically, &lt;b&gt;J&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;R&lt;/i&gt;&lt;/sup&gt;] is evaluated fully numerically [with the multipole expansion of the Coulomb potential (MECP)] during the SCF iterations. Upon convergence, &lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;R&lt;/i&gt;&lt;/sup&gt; is further split into those of near (&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;RC&lt;/i&gt;&lt;/sup&gt;) and distant (&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;RL&lt;/i&gt;&lt;/sup&gt;) atomic orbital (AO) pairs, such that &lt;b&gt;J&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;RC&lt;/i&gt;&lt;/sup&gt;] and &lt;b&gt;J&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;RL&lt;/i&gt;&lt;/sup&gt;] are evaluated seminumerically and fully numerically (with MECP). Such a hybrid &lt;b&gt;J&lt;/b&gt;-build is dubbed \"analytic-MECP\" (aMECP). Likewise, the analytic evaluation of &lt;b&gt;K&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sub&gt;⊕&lt;/sub&gt;&lt;sup&gt;&lt;i&gt;A&lt;/i&gt;&lt;/sup&gt;] and seminumerical evaluation of &lt;b&gt;K&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;R&lt;/i&gt;&lt;/sup&gt;] are also invoked for the construction of the exchange matrix &lt;b&gt;K&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;] during the SCF iterations. The chain-of-spheres (COSX) algorithm [Chem. Phys. 356, 98 (2009]) is employed for &lt;b&gt;K&lt;/b&gt;[&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;R&lt;/i&gt;&lt;/sup&gt;] but with a revised construction of the S-junctions for overlap AO pairs. To distinguish from the original COSX algorithm (which does not involve the partition of the density matrix &lt;b&gt;D&lt;/b&gt;), we denote the presently revised variant as COSx. Upon convergence, &lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;R&lt;/i&gt;&lt;/sup&gt; is further split into those of near (&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;RC&lt;/i&gt;&lt;/sup&gt;) and distant (&lt;b&gt;D&lt;/b&gt;&lt;sup&gt;&lt;i&gt;RL&lt;/i&gt;&lt;/sup&gt;) AO pairs followed by a rescaling, leading to &lt;math&gt;&lt;msup&gt;&lt;mover&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;mo&gt;~&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;C&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt; and &lt;math&gt;&lt;msup&gt;&lt;mover&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;mo&gt;~&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;, respectively. &lt;math&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;[&lt;/mo&gt;&lt;msup&gt;&lt;mover&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;mo&gt;~&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;C&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mo&gt;]&lt;/mo&gt;&lt;/mrow&gt;&lt;/math&gt; and &lt;math&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;[&lt;/mo&gt;&lt;msup&gt;&lt;mover&gt;&lt;mi&gt;D&lt;/mi&gt;&lt;mo&gt;~&lt;/mo&gt;&lt;/mover&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mo&gt;]&lt;/mo&gt;&lt;/mrow&gt;&lt;/math&gt; are then evaluated analytically and seminumerically (with COSx), respectively. Such a hybrid &lt;b&gt;K&lt;/b&gt;-build is dubbed \"analytic-COSx\" (aCOSx). Extensive numerical experimentations reveal that the combination of aMECP and aCOSx is highly accurate for ground state SCF calculations (&lt;math&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;msub&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mtext&gt;atom&lt;/mtext&gt;&lt;/math&gt; error in energy) and is particularly efficient for calculations of large molecules with extended basis sets. As for TDDFT excitation energies, a medium grid for MECP and a ","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143021334","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":"Enhanced Near-Infrared Fluorescence Emission near a Graphene-Metal Hybrid Structure.","authors":"Xiaowei Wang, Zhihui Chen, Guang Feng, Qiang Wang, Qinsong Yao, Yang Wang, Zhiyuan Wang, Yibiao Yang","doi":"10.1021/acs.jpca.4c06433","DOIUrl":"10.1021/acs.jpca.4c06433","url":null,"abstract":"<p><p>Plasmon resonance plays an important role in improving the detection of biomolecules, and it is one of the focuses of research to use metal plasmon resonance to achieve fluorescence enhancement and to improve detection sensitivity. However, the problems of nondynamic tuning and fluorescence quenching of metal plasmon resonance need to be solved. Graphene surface plasmon resonance can be dynamically controlled, and the graphene adsorption of fluorescent molecules can avoid fluorescence quenching and greatly improve the fluorescence emission intensity. The graphene-metal hybrid structure designed in this work can solve the above two problems well, and the plasmon resonance can improve the fluorescence emission efficiency of molecules on the surface of graphene and improve the sensitivity of biological detection. At the same time, graphene nanoribbons in our hybrid structure do not require patterning, which greatly lowers the threshold for graphene application in biosensing.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"677-685"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941471","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":"Top-Down versus Bottom-Up Approaches for σ-Functionals Based on the Approximate Exchange Kernel.","authors":"Yannick Lemke, Christian Ochsenfeld","doi":"10.1021/acs.jpca.4c05289","DOIUrl":"10.1021/acs.jpca.4c05289","url":null,"abstract":"<p><p>Recently, we investigated a number of so-called σ- and τ-functionals based on the adiabatic-connection fluctuation-dissipation theorem (ACFDT); particularly, extensions of the random phase approximation (RPA) with inclusion of an exchange kernel in the form of an antisymmetrized Hartree kernel. One of these functionals, based upon the approximate exchange kernel (AXK) of Bates and Furche, leads to a nonlinear contribution of the spline function used within σ-functionals, which we previously avoided through the introduction of a simplified \"top-down\" approach in which the σ-functional modification is inserted a posteriori following the analytic coupling strength integration within the framework of the ACFDT and which was shown to provide excellent performance for the GMTKN55 database when using hybrid PBE0 reference orbitals. In this work, we examine the analytic \"bottom-up\" approach in which the spline function is inserted a priori, i.e., before evaluation of the analytic coupling strength integral. The new bottom-up functionals, denoted σ↑AXK, considerably improve upon their top-down counterparts for problems dominated by self-interaction and delocalization errors. Despite a small loss of accuracy for noncovalent interactions, the σ↑AXK@PBE0 functionals comprehensively outperform regular σ-functionals, scaled σ-functionals, and the previously derived σ+SOSEX- and τ-functionals in the WTMAD-1 and WTMAD-2 metrics of the GMTKN55 database.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"774-787"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941522","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":"Evaporation Kinetics and Final Particle Morphology of Multicomponent Salt Solution Droplets.","authors":"Barnaby E A Miles, Emily Winter, Shaira Mirembe, Daniel Hardy, Lukesh K Mahato, Rachael E H Miles, Jonathan P Reid","doi":"10.1021/acs.jpca.4c07439","DOIUrl":"10.1021/acs.jpca.4c07439","url":null,"abstract":"<p><p>In both nature and industry, aerosol droplets contain complex mixtures of solutes, which in many cases include multiple inorganic components. Understanding the drying kinetics of these droplets and the impact on resultant particle morphology is essential for a variety of applications including improving inhalable drugs, mitigating disease transmission, and developing more accurate climate models. However, the previous literature has only focused on the relationship between drying kinetics and particle morphology for aerosol droplets containing a single nonvolatile component. Here we investigate the drying kinetics of NaCl-(NH₄)₂SO₄, NaCl-NH₄NO₃, and NaCl-CaCl₂ mixed salt aqueous aerosol droplets (25-35 μm radius) and the resulting morphology and composition of the dried microparticles. A comparative kinetics electrodynamic balance was used to measure evaporation profiles for each mixed salt aerosol at a range of relative humidities (RH) (0-50% RH); measurements of the evaporation kinetics are shown to be consistent with predictions from the \"Single Aerosol Drying Kinetics and Trajectories\" model. Populations of the mixed salt droplets were dried in a falling droplet column under different RH conditions and imaged using scanning electron microscopy to observe the impact of the drying kinetics on the morphology. Energy dispersive spectroscopy was used in tandem to obtain atomic maps and view the impact of drying kinetics on the composition of the resultant particles. It has been shown that the relationship between drying kinetics and dry particle morphology in mixed salt solution droplets is compositionally dependent and determined by the predominant salts that crystallize (i.e., (NH₄)₂SO₄, Na₂SO₄, or NaCl). The degree of homogeneity in composition throughout the particle microstructure is dependent on the drying rate.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"762-773"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142963377","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":"Autobiography of Richard J. Saykally.","authors":"Richard J Saykally","doi":"10.1021/acs.jpca.4c08426","DOIUrl":"https://doi.org/10.1021/acs.jpca.4c08426","url":null,"abstract":"","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"129 3","pages":"645-649"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143021256","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":"Introducing GPU Acceleration into the Python-Based Simulations of Chemistry Framework.","authors":"Rui Li, Qiming Sun, Xing Zhang, Garnet Kin-Lic Chan","doi":"10.1021/acs.jpca.4c05876","DOIUrl":"https://doi.org/10.1021/acs.jpca.4c05876","url":null,"abstract":"<p><p>We introduce the first version of GPU4PySCF, a module that provides GPU acceleration of methods in PySCF. As a core functionality, this provides a GPU implementation of two-electron repulsion integrals (ERIs) for contracted basis sets comprising up to <i>g</i> functions using the Rys quadrature. As an illustration of how this can accelerate a quantum chemistry workflow, we describe how to use the ERIs efficiently in the integral-direct Hartree-Fock build and nuclear gradient construction. Benchmark calculations show a significant speedup of 2 orders of magnitude with respect to the multithreaded CPU Hartree-Fock code of PySCF and the performance comparable to other open-source GPU-accelerated quantum chemical packages, including GAMESS and QUICK, on a single NVIDIA A100 GPU.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143021336","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":"Submillimeter-Wave Spectroscopy of the CH₃O Radical.","authors":"Marie-Aline Martin-Drumel, Jean-Thibaut Spaniol, Olivia Chitarra, Olivier Pirali, Holger S P Müller","doi":"10.1021/acs.jpca.4c07638","DOIUrl":"10.1021/acs.jpca.4c07638","url":null,"abstract":"<p><p>The methoxy radical, CH₃O, has long been studied experimentally and theoretically by spectroscopists because it displays a weak Jahn-Teller effect in its electronic ground state, combined with a strong spin-orbit interaction. In this work, we report an extension of the measurement of the pure rotational spectrum of the radical in its vibrational ground state in the submillimeter-wave region (350-860 GHz). CH₃O was produced by H-abstraction from methanol using F atoms, and its spectrum was probed in absorption using an association of source-frequency modulation and Zeeman modulation spectroscopy. All the observed transitions together with available literature data in ν = 0 were combined and fit using an effective Hamiltonian allowing to reproduce the data at their experimental accuracy. The newly measured transitions involve significantly higher frequencies and rotational quantum numbers than those reported in the literature (<i>f</i> < 860 GHz and <i>N</i> ≤ 15 instead of 372 GHz and 7, respectively), which results in significant improvements in the spectroscopic parameters determination. The present model is well constrained and allows a reliable calculation of the rotational spectrum of the radical over the entire microwave to submillimeter-wave domain. It can be used with confidence for future searches of CH₃O in the laboratory and in the interstellar medium.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"754-761"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142961998","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":"Self-consistent Quantum Linear Response with a Polarizable Embedding Environment.","authors":"Peter Reinholdt, Erik Kjellgren, Karl Michael Ziems, Sonia Coriani, Stephan P A Sauer, Jacob Kongsted","doi":"10.1021/acs.jpca.4c07534","DOIUrl":"https://doi.org/10.1021/acs.jpca.4c07534","url":null,"abstract":"<p><p>Quantum computing presents a promising avenue for solving complex problems, particularly in quantum chemistry, where it could accelerate the computation of molecular properties and excited states. This work focuses on computing excitation energies with hybrid quantum-classical algorithms for near-term quantum devices, combining the quantum linear response (qLR) method with a polarizable embedding (PE) environment. We employ the self-consistent operator manifold of quantum linear response (q-sc-LR) on top of a unitary coupled cluster (UCC) wave function in combination with a Davidson solver. The latter removes the need to construct the entire electronic Hessian, improving computational efficiency when going toward larger molecules. We introduce a new superposition-state-based technique to compute Hessian-vector products and show that this approach is more resilient toward noise than our earlier gradient-based approach. We demonstrate the performance of the PE-UCCSD model on systems such as butadiene and para-nitroaniline in water and find that PE-UCCSD delivers comparable accuracy to classical PE-CCSD methods on such simple closed-shell systems. We also explore the challenges posed by hardware noise and propose simple error mitigation techniques to maintain accurate results on noisy quantum computers.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143027476","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":"Quadrupole-Central-Transition ²³Na, ³⁹K, ⁸⁷Rb NMR Studies of Alkali Metal Ions under Different Molecular Tumbling Conditions: A Simple Model to Treat Chemical Exchange Involving Quadrupolar Nuclei.","authors":"Ziyao Peng, Gang Wu","doi":"10.1021/acs.jpca.4c07473","DOIUrl":"10.1021/acs.jpca.4c07473","url":null,"abstract":"<p><p>We report a new NMR method for treating two-site chemical exchange involving half-integer quadrupolar nuclei in a solution. The new method was experimentally verified with extensive ²³Na (<i>I</i> = 3/2), ³⁹K (<i>I</i> = 3/2), and ⁸⁷Rb (<i>I</i> = 3/2) NMR results from alkali metal ions (Na⁺, K⁺, and Rb⁺) in a solution over a wide range of molecular tumbling conditions. In the fast-motion limit, all allowed single-quantum NMR transitions for a particular quadrupolar nucleus are degenerate giving rise to one Lorentzian signal. In the slow-motion regime, although the NMR signal from quadrupolar nuclei should in principle exhibit a multi-Lorentzian line shape, only the quadrupole central transition (QCT) is often detectable in practice. In all the cases studied in this work, we found that alkali metal ions undergo fast exchange between free and bound states. Using the new theoretical method, we were able to interpret the experimental transverse relaxation data (i.e., line widths) obtained for ²³Na, ³⁹K, and ⁸⁷Rb NMR signals including QCT signals over a large temperature range and extract information about ion-binding dynamics in different chemical environments. This work fills a gap in the literature where a unified approach for treating NMR transverse relaxation data for quadrupolar nuclei over the entire range of motion has been lacking. Our results suggest that the new approach is applicable in the study of alkali metal ion binding to biological macromolecules.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":" ","pages":"803-813"},"PeriodicalIF":2.7,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941499","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}