International Journal of Quantum Chemistry最新文献

{"title":"Compact Vibrational Wave Functions via Linear Optimization","authors":"Anna Kelemen,&nbsp;Sandra Luber","doi":"10.1002/qua.70177","DOIUrl":"https://doi.org/10.1002/qua.70177","url":null,"abstract":"<div>\u0000 \u0000 <p>We present a deterministic all-parameter optimization method based on analytic derivatives for vibrational wave functions in a separable product form represented in a distributed Gaussian basis. The optimization of the center and width parameters of the basis allows for compact wave function representations at a small basis size. We illustrate the approach by computing ground and excited vibrational states of anharmonic model systems and the 9-dimensional formic acid monomer.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147696388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interpretable Machine Learning for Benchmarking DFT Electron Affinity Predictions: A Generalized Additive Model Approach","authors":"Ismail Badran,&nbsp;Abdelrahman Eid,&nbsp;Motasem Far,&nbsp;Nadeen Abbas,&nbsp;Raghad Tayeh,&nbsp;Sahar Salman,&nbsp;Yasmeen Hamdan","doi":"10.1002/qua.70189","DOIUrl":"https://doi.org/10.1002/qua.70189","url":null,"abstract":"<div>\u0000 \u0000 <p>Electron affinity (EA) is vital for understanding charge transfer, redox reactions, and material design across chemistry and materials science. This study introduces a novel methodology that integrates interpretable machine learning with density functional theory (DFT) to provide a guideline for EA predictions. Using Generalized Additive Models (GAM), we reveal how functionals, basis sets, and molecular species interact in complex and nonlinear ways, offering insights that are not accessible through conventional analyses. A curated dataset of 47 atoms and molecules was used to assess the predictive performance of nine functionals across five basis sets. The results show that basis set selection has a more pronounced effect on EA prediction accuracy than functional choice, with the “<i>augmented</i>” ma-def2-SVP basis set, particularly in combination with B3LYP, providing the most reliable predictions. In contrast, the “<i>unaugmented</i>” def2-TZVP and def2-SVP basis sets frequently introduced large errors and high variability. The GAM framework identified species-specific challenges, especially for Cl₂, NH₃, and CN, and demonstrated that although statistically significant differences exist among functionals, their performance in predicting EA values is largely equivalent from a chemical perspective. The GAM-based ranking showed a spread of 1.6 kJ/mol among the average predicted deviations of the tested functionals, indicating that their practical differences are small from a chemical perspective under the studied conditions. This interpretable machine learning approach therefore provides a transparent and reproducible strategy for guiding the selection of DFT methods for EA calculations. To our knowledge, this is the first study to apply interpretable ML to systematically investigate and challenge generalized assumptions in EA benchmarking, establishing a data-driven framework for practical decision-making in computational chemistry.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147696387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational and Spectroscopic Insights Into the Rice Bran Derived Glu-Gln-Arg-Pro-Arg Pentapeptide as an Anticancer Agent: A DFT, Molecular Docking, and Molecular Dynamics Study","authors":"Gozde Yilmaz,&nbsp;Sefa Celik,&nbsp;Aysen E. Ozel,&nbsp;Sevim Akyuz","doi":"10.1002/qua.70190","DOIUrl":"https://doi.org/10.1002/qua.70190","url":null,"abstract":"<p>In this study, we present detailed results on the molecular structure, vibrational frequencies, and bioactivity of the neutral L-Glu-L-Gln-L-Arg-L-Pro-L-Arg (EQRPR) pentapeptide, derived from rice bran, which exhibits anti-cancer, anti-Alzheimer's, and anti-obesity properties. Theoretical conformational analysis was performed to evaluate the conformational preferences of the pentapeptide. The most stable conformer was then optimized at the DFT/b3lyp/6–31G(d,p), DFT/b3lyp/6–31 + G(d,p), and DFT/wb97xd/6–31++G(d,p) levels of theory. The experimental FTIR and Raman spectra were compared with the theoretically predicted vibrational spectra at these levels. As the DFT/wb97xd/6–31++G(d,p) results showed the closest agreement with the experimental data, all subsequent calculations were performed using this level of theory. The molecular electrostatic potential (MEP) and frontier molecular orbitals were calculated using the optimized pentapeptide structure to evaluate its chemical reactivity. To investigate its potential biological activity as an anticancer and antiviral agent, molecular docking studies were performed against 1BNA, 4HJO, 1JV2, 3ZDX, 4WK0, 6 M03, 6 LU7, and 6VXX targets. Among these, the EQRPR pentapeptide exhibited the strongest binding affinity toward <i>α</i>₅<i>β</i>₁ integrin (4WK0; ∆<i>G</i> = −9.3 kcal/mol). Furthermore, following the docking calculations, the best conformation of the EQRPR-<i>α</i>₅<i>β</i>₁ integrin complex was subjected to 200 ns of all-atom molecular dynamics simulations. The MD results indicate the stability of the EQRPR-4WK0 complex, and the binding free energy was determined from the simulation results using the Molecular Mechanics/Poisson-Boltzmann Surface Area (MM-PBSA) method as −72.9895 kcal/mol. Overall, these results suggest that the neutral EQRPR pentapeptide possesses broad therapeutic potential and may serve as a promising candidate for the development of antiviral and anticancer agents.</p>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qua.70190","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147696287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unlocking Giant Two-Photon Absorption Through Iodine Coordination in A-π-D-π-A Carbazole-Based Probes","authors":"Xue Sun,&nbsp;Yaochuan Wang,&nbsp;Haoran Ni,&nbsp;Jiuqi Yang,&nbsp;Yizhuo Wang,&nbsp;Yu Li,&nbsp;Dajun Liu,&nbsp;Xuesong Xu,&nbsp;Maodu Chen","doi":"10.1002/qua.70187","DOIUrl":"https://doi.org/10.1002/qua.70187","url":null,"abstract":"<div>\u0000 \u0000 <p>The strategic modulation of two-photon absorption (TPA) in A-π-D-π-A carbazole-based probes, achieved through N-methylation of terminal pyridine groups and subsequent iodide ion coordination, is unveiled by density functional theory (DFT)/TD-DFT calculations. We demonstrate that methylation transforms pyridine into pyridinium nitrogen, markedly enhancing intramolecular charge transfer efficiency. The subsequent introduction of iodide ions uniquely coordinates with the pyridinium nitrogen, triggering a dramatic surge in the long-wavelength TPA cross-section. This enhancement is primarily attributed to a resonant one-step TPA transition mechanism. Our findings establish a potent strategy for the rational design of high-performance biological imaging probes with tailored response wavelengths.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147696330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Hybrid Convolutional Neural Network and Grid Extrapolation Approach for Predicting Solutions of the Electronic Schrödinger Equation","authors":"Achmad Jaelani,&nbsp;Muhammad Aziz Majidi,&nbsp;Rui-Qin Zhang,&nbsp;Yanoar Pribadi Sarwono","doi":"10.1002/qua.70185","DOIUrl":"https://doi.org/10.1002/qua.70185","url":null,"abstract":"<div>\u0000 \u0000 <p>Solving the many-electron Schrödinger equation is central to numerous branches of physics, yet its computational complexity often poses challenges. In this work, we explore the integration of deep learning techniques to predict electronic properties for model systems, focusing on two distinct cases: (1) single-electron properties from three-dimensional (3D) potential representations, and (2) two-electron properties of the hydrogen molecule (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {mathrm{H}}_2 $$</annotation>\u0000 </semantics></math>) in six-dimensional (6D) space. Our 3D model utilizes a deep convolutional neural network architecture to handle cubic potential inputs, while our 6D extension employs a modified architecture for the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {mathrm{H}}_2 $$</annotation>\u0000 </semantics></math> system. We augment our datasets with random rotations to address rotational invariance. Through comprehensive experiments, we demonstrate the effectiveness of our approach across dimensionalities. For the 6D case, we achieve high accuracy by using the network to predict grid-dependent energies, which are then refined with a polynomial extrapolation scheme. This hybrid approach highlights deep learning's potential as a powerful accelerator for traditional grid-based numerical methods in electronic structure calculations.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147668213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three Methods to Identify and Visualize Nonuniform Changes in Interatomic Interactions: Second-Difference Analysis, Anharmonicity Inversion, and Distance-Dependent NMR Absolute Shieldings","authors":"Ilya G. Shenderovich,&nbsp;Gleb S. Denisov","doi":"10.1002/qua.70184","DOIUrl":"https://doi.org/10.1002/qua.70184","url":null,"abstract":"<p>Vibrational excitation of chemical bonds induces nonuniform distortions in the potential energy surface that reflect changes in interatomic interactions. These qualitative changes can be identified and visualized using three complementary methods. The second-difference analysis, tracking successive vibrational energy gaps, applies when all vibrational level energies and the dissociation limit are known. The anharmonicity-inversion method uses a Morse potential and requires only the vibrational energy gaps 0 → 1 and 1 → 2, along with the dissociation limit, to reveal anomalous local anharmonicity near the first excited vibrational level by comparing the Morse-predicted bond energy with the true bond energy. Finally, NMR shielding-tensor mapping permits identification of interatomic distances at which the electronic environment undergoes qualitative changes, without requiring prior knowledge of the potential. Applied to the diatomic cations C⁺–Ng and H⁺–Ng (Ng = He, Ne, and Ar), all three approaches consistently delineate specific vibrational-state or internuclear distance regions where the character of the interatomic interaction changes noticeably.</p>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qua.70184","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147668957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spin Crossover in the Cis-[CoII/III(bpym)2(–NCSe)2]0/+ Complexes","authors":"Kobra Salabat,&nbsp;Hassan Sabzyan","doi":"10.1002/qua.70158","DOIUrl":"https://doi.org/10.1002/qua.70158","url":null,"abstract":"<div>\u0000 \u0000 <p>Spin crossover (SCO) in <i>cis-</i>[Co^II/III(bpym)₂(–NCSe)₂]^0/+ complexes is studied using density functional theory UB3LYP/cc-PVDZ[LANL2DZ] method. Analysis of normal vibrational modes and the corresponding frequencies and IR spectra calculated for these complexes in their more stable high-spin (HS) and less stable low-spin (LS) states shows that the HS ↔ LS spin transition has significant effects on the vibrational modes belonging to the regions with significant electron density redistribution. Analysis of the Duschinsky matrix calculated for the HS ↔ LS SCO in these complexes shows that most of mode mixing occur around the diagonal, and the extent of Duschinsky mixing during HS ↔ LS SCO is correlated with the corresponding atomic charge (electron density) redistribution. Analysis of the index, defined based on the Duschinsky matrix elements to quantify the overall vibrational mode mixing shows that the mode mixing due to HS ↔ LS SCO is larger for the [Co^III(bpym)₂(–NCSe)₂]⁺ than that for the [Co^II(bpym)₂(–NCSe)₂] complex, which is compatible with the larger variations of the atomic charges of the former complex in its SCO conversion. The transition state of the HS ↔ LS SCO in the [Co^III(bpym)₂(–NCSe)₂]⁺ complex is located using QST2 method, and characterized.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147668936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantum Chemical Insights Into Noncovalent Interactions Between Aromatic Heterocycles and Formic Acid","authors":"Haimyapriya Buragohain,&nbsp;Vinod Kumar,&nbsp;Ramesh C. Deka,&nbsp;Kaushik Talukdar","doi":"10.1002/qua.70182","DOIUrl":"https://doi.org/10.1002/qua.70182","url":null,"abstract":"<div>\u0000 \u0000 <p>We employ various electronic structure methods to explore the noncovalent interactions in the formic acid (FA)–aromatic heterocycle (ZC₄H₄, where ZO, S and Se) dimers. The interaction energy (<i>E</i>_int) of these dimeric complexes is calculated within the supermolecular approach and the symmetry-adapted perturbation theory (SAPT). We also investigate the effects of electron correlation and basis set size on the computation of <i>E</i>_int. Our study reveals that furan (OC₄H₄) prefers to interact with formic acid via the nonbonding electron of the O atom, whereas thiophene (SC₄H₄) and selenophene (SeC₄H₄) do the same via <i>π</i>-electrons. Although there is an interplay of charge transfer from the nonbonding- and <i>π</i>-orbital of the aromatic heterocycle moieties to the antibonding orbital of the O<span></span>H bond in the formic acid, the complexes are primarily stabilized by electrostatic and dispersion forces. The quantum theory of atoms in molecule (QTAIM) analysis further confirms that these complexes involve closed-shell interactions, particularly moderate-strength hydrogen bonding.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147668648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectroscopic and Collision Excitation Process for Li Atom Confined in a Gaussian Well With Application to Fullerene Confinement","authors":"Zhanbin Chen","doi":"10.1002/qua.70183","DOIUrl":"https://doi.org/10.1002/qua.70183","url":null,"abstract":"<div>\u0000 \u0000 <p>We report a detailed investigation of the spectral characteristics, electron-impact excitation dynamics, and de-excitation radiation processes of a lithium atom confined inside a <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>C</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>60</mn>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {C}_{60} $$</annotation>\u0000 </semantics></math> fullerene cage. To this end, we propose a fully relativistic approach based on the Dirac-Coulomb Hamiltonian within a configuration-interaction framework. The confining effect of the cage is modeled using a power-exponential-model potential. Solutions of the modified Dirac equations provide both bound and continuum state wave functions. A feature of our approach is the replacement of the standard Coulomb interaction with a combined Coulomb potential and Breit interaction in the calculation of scattering matrix elements. As a representative application, we present detailed calculations of the Gaussian well with spherical confinement effects on the energy levels, transition probabilities, wave functions, total cross sections, magnetic cross sections, linear polarization of the radiation, and angular distribution of emitted photons for a Li atom inside <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mi>C</mi>\u0000 </mrow>\u0000 <mrow>\u0000 <mn>60</mn>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {C}_{60} $$</annotation>\u0000 </semantics></math>. Our predictions agree closely with other studies, demonstrating the reliability of the method and its potential usefulness in atomic physics, radiation physics, quantum chemistry, and materials science.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147579822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On Degree-Based Topological Indices and QSPR Analysis of Some Novel Drugs Used in the Treatment of Cervical Cancer Using Machine Learning With XGBoost and Regression Models","authors":"Uma Ramachandran,&nbsp;N. Kavitha,&nbsp;H. Naresh Kumar","doi":"10.1002/qua.70180","DOIUrl":"https://doi.org/10.1002/qua.70180","url":null,"abstract":"<div>\u0000 \u0000 <p>Topological indices (TIs), derived from molecular graph theory, serve as valuable tools in the evaluation of drug efficacy for cervical cancer treatment. These indices capture essential structural information that aids in predicting therapeutic potential and assessing toxicity, both of which are critical for the development of safe and effective anticancer agents. This study introduces a Quantitative Structure-Property Relationship (QSPR)-based approach that integrates TIs with molecular features to estimate key physicochemical properties, including boiling point (BP), melting point (MP), enthalpy of vaporization (EV), flash point (FP), index of refraction (IR), molar refractivity (MR), molar volume (MV), polarizability (P), surface tension (ST) and polar surface area (PSA). A linear regression (LR) model is constructed using these features and benchmarked against an Extreme Gradient Boosting (XGBoost) model. Comparative analysis reveals that the XGBoost model significantly enhances prediction accuracy over traditional regression methods. The findings highlight the effectiveness of combining machine learning techniques with topological descriptors in enhancing predictive modeling for drug discovery in cervical cancer.</p>\u0000 </div>","PeriodicalId":182,"journal":{"name":"International Journal of Quantum Chemistry","volume":"126 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2026-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147615102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}