Journal of Molecular Modeling最新文献

{"title":"Screening of ionic liquids as sustainable catalyst for production of n-butyl acetate using COSMO-RS model.","authors":"Anantharaj Ramalingam, Achsah Rajendran Startha Christabel, Gayathri Mahavishnu","doi":"10.1007/s00894-025-06434-4","DOIUrl":"https://doi.org/10.1007/s00894-025-06434-4","url":null,"abstract":"<p><strong>Context: </strong>A total of 42 cations and 32 anions resulting in 1344 possible combinations were screened for green esterification process via the conductor-like screening model for real solvents (COSMO-RS model). The esterification reactants and products; n-butanol (n-BuOH), acetic acid (HAc), and n-butyl acetate (n-BuAc) in different combination of cation and anions were used to predict the activity coefficient at infinite dilution (IDAC) with the help of screening charge density. From the predicted IDAC values, the selectivity (S), capacity (C), and performance index (PI) were calculated to screen potential ionic liquids (ILs) for the green esterification process. Further, the σ-profile, and σ-potential of ILs, reactants, and products were generated and analysed.</p><p><strong>Methods: </strong>Molden Visualization Software, Gaussian 03 software, COSMOthermX (Version:19.0.5) were used to predict IDAC, sigma profile, and sigma potential. Hartree-Fock level and basis set 6-31G*. Density functional theory (DFT) with PBVP86 in combination with the basis set SVP (split valence polarised) and the density fitting basis set DGA1 (density gradient approximation)-#P BVP86/SVP/DGA1.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 8","pages":"208"},"PeriodicalIF":2.1,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Separation mechanism and chiral-HPLC chromatogram profile of racemic mandelate compounds: a comparative study between experiment and computation using conformer-rotamer ensemble sampling tool (CREST)-XTB.","authors":"Fenti Fatmawati, Aditya Wibawa Sakti, Suci Zulaikha Hildayani, Akhmaloka, Fida Madayanti Warganegara, Muhamad Abdulkadir Martoprawiro","doi":"10.1007/s00894-025-06408-6","DOIUrl":"https://doi.org/10.1007/s00894-025-06408-6","url":null,"abstract":"<p><strong>Context: </strong>Nearly 90% of drugs on the market are racemates. A racemate is a mixture of two enantiomers or substances in equal amounts that have an asymmetric molecular structure that is a mirror image of each other. Despite having the same chemical structure, chiral drug isomers can exhibit very different biological behaviors in terms of pharmacology, toxicity, pharmacokinetics, metabolism, etc. Since racemic drugs have only one bioactive enantiomer while its counterpart enantiomers impart undesirable pharmacological properties, it is necessary to separate these racemic compounds to obtain the desired active enantiomer. Chromatography is one of the approaches for the separation of enantiomers. In this study, we observed the chromatographic profile of racemic mandelic acid compound passed through a chiral HPLC column. The chromatogram profile was then observed computationally to study the separation mechanism. The experimental results are in line with the computational analysis that the S chromatogram eluted first compared to the R-enantiomer. It can be predicted that the binding energy of the R-enantiomer (-108.92 kJ/mol) is stronger than the S-enantiomer (- 67 kJ/mol).</p><p><strong>Methods: </strong>The chromatogram profile of mandelic acid racemate was observed experimentally using a chiral OD column, and the prediction of column-ligand binding energy was based on computational studies using the conformer-rotamer ensemble sampling tool (CREST). The chromatogram profile was identified using a 0.46 cm × 25 cm chiral OD column HPLC instrument (Daicel Chemical). The samples used were racemic compounds of mandelic acid and standard (S)-mandelic acid. Computational calculations of column capacity factors and binding energies of each enantiomer were performed with a Windows 11 Pro 64-bit operating system, × 64-based processor, equipped with the MGL-Tools program consisting of the ADT (Autodock Tools) application, Avogadro, AutoDock 4.2, Discovery Studio 2020 Client®, and CREST installed as a driver program for the XTB semiempirical quantum chemistry package. For geometry optimization and sampling of DMPC-ligand complexes, we used CREST at https://github.com/grimme-lab/crest .</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 8","pages":"206"},"PeriodicalIF":2.1,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of enzyme inhibition (IC₅₀) using a combination of protein-ligand docking and semiempirical quantum mechanics.","authors":"Robert C Glen, Jason C Cole, James J P Stewart","doi":"10.1007/s00894-025-06423-7","DOIUrl":"10.1007/s00894-025-06423-7","url":null,"abstract":"<p><strong>Context: </strong>The ability to predict the relative binding energies of ligands to a biological receptor would be of great value in drug discovery. However, accurately calculating the predicted binding energies is limited by the high accuracy required, by the presence of multiple minima on the potential energy surface, and by issues specific to the intrinsic properties of the binding site, such as details of the geometry of the ligand-protein complex. To address these issues, a systematic analysis of potential sources of error was carried out which resulted in a few relatively small changes being made to the MOPAC program.</p><p><strong>Methods: </strong>A set of 77 ligands was constructed for which experimentally determined IC₅₀ values were available. For each of the ligands, prediction of the protein-ligand interaction energy was carried out in two distinct stages. In the first stage, the Protein-Ligand docking program GOLD was used to generate several distinct conformations of the ligand bound to a protein. The geometries of these systems were then optimised using the MOPAC program. A comparison of the relative binding energies of the ligands with the reported IC₅₀ values showed a very poor predictive power. By partitioning the ligand set into two subsets, and eliminating six ligands that were inconsistent with the experimental results, a large increase in accuracy was obtained.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 8","pages":"209"},"PeriodicalIF":2.1,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12255584/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ab initio prediction for product stereo-specificity in the CH₃CHI + O₂ reaction: formation of syn- vs anti-CH₃CHOO.","authors":"Hue-Phuong Trac, Putikam Raghunath, Ming-Chang Lin","doi":"10.1007/s00894-025-06426-4","DOIUrl":"10.1007/s00894-025-06426-4","url":null,"abstract":"<p><strong>Context: </strong>The stereo-specific production of syn- and anti-CH₃CHOO conformers from the CH₃CHI + O₂ reaction has been investigated by ab initio quantum-chemical and statistical theory studies. The results of the studies clearly indicate that the [syn]:[anti] product ratio depends on both temperature and pressure of the reaction system, and is kinetically, rather than thermodynamically, controlled. Most experimental data measured near room temperature at 2-10 Torr He pressure agree with the predicted results in terms of either the absolute rate constants for syn- and anti-CH₃CHOO production and/or the [syn]:[anti] product ratio. If the stereo-specificity of syn- and anti-CH₃CHOO formation were controlled thermodynamically, one would predict [syn]:[anti] = 241:1 independent of pressure at 298 K, instead of (80 ± 10):(20 ± 10) measured experimentally or 86:14 predicted theoretically at 5-Torr He pressure.</p><p><strong>Methods: </strong>All calculations were performed using Gaussian 16 software. Geometry, frequency, and IRC analysis calculations were conducted at the B3LYP/Aug-cc-PVTZ level of theory. The potential energy surface of the system was computed at the CCSD(T)/Aug-cc-PVTZ//B3LYP/Aug-cc-PVTZ level. The rate constants for individual product channels in the reaction, including the direct production of IO + CH₃CHO and the collisional deactivation of the excited CH₃CHIO₂* intermediate formed by the association of CH₃CHI with O₂, were predicted by statistical theory calculations using the Variflex code.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 8","pages":"205"},"PeriodicalIF":2.1,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12254064/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regioisomerism effects on the thermal decomposition mechanism of fused triazole-based high-nitrogen compounds: a DFT study.","authors":"Zhihui Gu, Mengjie Bo, Zikai Gao, Congming Ma, Peng Ma","doi":"10.1007/s00894-025-06427-3","DOIUrl":"https://doi.org/10.1007/s00894-025-06427-3","url":null,"abstract":"<p><strong>Context: </strong>High-nitrogen fused-ring compounds are promising candidates for energetic materials due to their high energy density and good thermal stability. As a molecular design strategy, regioisomerism has been widely applied in pharmaceuticals and functional materials. However, its effect on the performance of high-nitrogen fused energetic materials has not yet been systematically investigated. In this study, density functional theory (DFT) was employed to explore the structural and energetic implications of regioisomerism by examining four representative compounds: 3-nitro-1H-[1,2,4]triazolo[4,3-b][1,2,4]triazole (A1), 6-nitro-1H-[1,2,4]triazolo[4,3-b][1,2,4]triazole (A2), [1,2,4]triazolo[4,3-a][1,3,5]triazine-3,5,7-triamine (B1), and [1,2,4]triazolo[1,5-a][1,3,5]triazine-2,5,7-triamine (B2). A comparative analysis was conducted from multiple perspectives, including molecular conformation, bond strength, non-covalent interactions, and surface electrostatic potential distributions. Computational results revealed notable differences among the regioisomers in terms of internal steric repulsion, key bond strength, and charge distribution, which in turn influenced their initial decomposition pathways and corresponding energy barriers. Specifically, A2 and B2 exhibited more compact molecular geometries, reduced intramolecular repulsion, and generally higher activation barriers along key bond cleavage pathways, indicating superior thermal stability compared to their respective isomers. This work highlights the important role of regioisomerism in tuning the thermal stability of high-nitrogen fused-ring energetic compounds and provides theoretical guidance for the rational design of high-performance energetic materials.</p><p><strong>Methods: </strong>All computations in this study were performed using Gaussian 16 at the M06-2X/def2-TZVPP level of theory. The intrinsic reaction coordinate (IRC) calculations were conducted to verify the validity of all transition states. The Shermo program was employed to compute the Gibbs free energy of the molecules, while wavefunction analysis was carried out using Multiwfn and VMD.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 8","pages":"204"},"PeriodicalIF":2.1,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144582780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interfacial behavior and diffusion mechanisms of BNi-2 brazing on titanium alloy: experimental and molecular dynamics insights.","authors":"Tansu Göynük, Ziya Esen, İshak Karakaya","doi":"10.1007/s00894-025-06429-1","DOIUrl":"10.1007/s00894-025-06429-1","url":null,"abstract":"<p><strong>Context: </strong>Joining titanium alloys, particularly Ti-6Al-4V, is crucial in aerospace applications where reliable, high-performance joints are needed. Brazing offers an effective solution, enabling the joining of dissimilar materials without melting the base metals. However, optimizing the wetting and diffusion behavior of filler metals remains a challenge. This study investigates the high-temperature interaction between BNi-2 filler alloy and Ti-6Al-4V. Boron, the primary melting point depressant in BNi-2, was examined due to its small atomic size and interstitial diffusion mechanism. Elevated temperatures led to improved wetting, reflected by decreased contact angles. Both wetting angles and boron diffusion coefficients were obtained through molecular dynamics simulations and experimental measurements, showing reasonable correlation. These results provide valuable insight into interfacial mechanisms and support further optimization of brazing parameters.</p><p><strong>Methods: </strong>Molecular dynamics simulations were performed using LAMMPS to analyze the temperature-dependent wetting behavior of molten BNi-2 on Ti-6Al-4V and track atomic-scale diffusion. Initial atomic configurations were modeled and simulated under various conditions. Trajectory data were analyzed using OVITO for structural evolution. Boron diffusion was evaluated by calculating mean square displacement from LAMMPS outputs. These values were used to derive diffusion coefficients and activation energies. Parallel experiments were conducted to assess wetting angles and diffusion behavior, and simulation results were compared with experimental data. The consistency between both approaches highlights the reliability of the modeling framework in capturing essential mechanisms during the brazing process.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 7","pages":"200"},"PeriodicalIF":2.1,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144525904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational investigation of electrocatalytic ammonia synthesis on Mo-doped C₂₄N₂₄ fullerene.","authors":"Muhammad Junaid, Sajid Karam, Muhammad Iqbal, Mehran Anjum","doi":"10.1007/s00894-025-06425-5","DOIUrl":"10.1007/s00894-025-06425-5","url":null,"abstract":"<p><strong>Context: </strong>The industrial production of ammonia through the Haber-Bosch process is energy intensive and operates under extreme conditions. In contrast, the catalytic reduction of nitrogen (N₂) to ammonia (NH₃) under mild conditions presents a significant challenge with important implications for sustainable chemistry. This work investigates the potential of Mo-doped carbon nitride (C₄₂N₂₄) fullerene as a catalyst for N₂ reduction. The study reveals that Mo@C₄₂N₂₄ exhibits rapid catalytic activity, with a preference for the enzymatic mechanism for N₂ conversion to NH₃. Notably, H₂ evolution is suppressed, making Mo-doped C₄₂N₂₄ a promising candidate for ammonia synthesis under mild conditions.</p><p><strong>Methods: </strong>Density functional theory (DFT) calculations were performed using the Perdew-Burke-Ernzerhof (PBE) functional within the generalized gradient approximation (GGA) framework. The DNP basis set was employed in all calculations using the DMol³ code. The Mo atom was incorporated into the N₄ cavity of the carbon nitride structure, with a binding energy of - 2.54 eV. The electronic structure was analyzed through molecular electrostatic potential maps, Hirshfeld charge density analysis, and spin density analysis. Three catalytic pathways, alternating, distal, and enzymatic were studied to understand the reaction mechanism. All calculations were carried out using the DMol³ software package.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 7","pages":"201"},"PeriodicalIF":2.1,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144525903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"QTAIM topological analyses of zinc(II), cadmium(II), and mercury(II) xanthate complexes.","authors":"Daniella B de Miranda, Henrique C Silva Junior, Glaucio B Ferreira","doi":"10.1007/s00894-025-06422-8","DOIUrl":"10.1007/s00894-025-06422-8","url":null,"abstract":"<p><strong>Context: </strong>Environmental contamination by heavy metals is increasing due to population growth and industrial activity, which is having a major impact on the environment. Xanthates, which form stable complexes with metals, are used to remove them from aqueous environments. Known for their role in ore flotation, these compounds also have applications in the biological field and thin film production. Due to the versatility of the coordination of xanthates to metal centers, it is essential to understand the nature of the metal-ligand bonds in these systems. Given their coordination versatility, understanding metal-ligand interactions is essential. Therefore, this study investigates the nature of the metal-ligand bonds of compounds containing n-propyl xanthate and water, with Zn²⁺, Cd²⁺, and Hg²⁺ ions. QTAIM analysis revealed that the metal-OH₂ bonds are predominantly electrostatic, while the metal-S bonds are partially covalent, with an increasing trend of covalency along group 12 (Zn²⁺ < Cd²⁺ < Hg²⁺), especially in the neutral and bidentate complexes, corroborating Pearson's theory.</p><p><strong>Methods: </strong>QTAIM analysis was carried out on 30 structures of n-propyl xanthate complexes with group 12 metals, which were previously investigated in earlier studies. These compounds had already been analyzed through energy decomposition analysis, providing a basis for comparison with the QTAIM results presented in this work. QTAIM was performed using wfx files generated at the DFT level (M06L/def2-TZVP) and analyzed with Multiwfn. Wavefunction (wfx) files, which contain detailed information on the electronic density distribution essential for accurate topological analysis, were generated and analyzed using Multiwfn to characterize the metal-ligand interactions.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 7","pages":"202"},"PeriodicalIF":2.1,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144525905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A DFT study of the hydrolytic degradation mechanisms of iprovalicarb and iprodione: implications in environmental safety.","authors":"Peter N Nelson","doi":"10.1007/s00894-025-06424-6","DOIUrl":"10.1007/s00894-025-06424-6","url":null,"abstract":"<p><strong>Context: </strong>Iprovalicarb and iprodione represent two popular carboxylic acid amide-type (CAA) fungicides which have found wide spread application in the protection of various crops. However, though useful, excessive usage of these compounds could have deleterious effects on human health and environmental safety. Hence, a thorough DFT investigation of the degradation thermodynamics and mechanism for these two compounds was carried out, revealing a multi-step hydrolytic transformation process in the gas phase via overall exergonic processes where the rate limiting steps are calculated at ca. 197 and 235 kJ mol^-1, for iprodione and iprovalicarb, respectively. However, in aqueous media, whereas for iprodione the hydrolysis mechanism is identical to that in the gas phase, for iprovalicarb, the endergonic solution phase mechanism is different. Overall, both compounds undergo very slow hydrolysis at neutral pH but, of the two, iprodione offers the shortest residence time.  METHODS: All calculations were carried out at the 6-311 +  + G(d,p)/CAM-B3LYP level of theory, as implemented in the Gaussian-16 software suite. Solution phase calculations were carried out via the well-regarded C-PCM model, an implicit solvation model, known to be efficient and effective at predicting solvation effects.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 7","pages":"203"},"PeriodicalIF":2.1,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144525902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geometric and electronic structures of FeB_n^-/0/+ clusters (n = 1-3): insights from advanced computational methods.","authors":"Hoang Lin Nguyen, Quoc Tri Tran, Kim Tai Dang, Van Tan Tran","doi":"10.1007/s00894-025-06428-2","DOIUrl":"10.1007/s00894-025-06428-2","url":null,"abstract":"<p><strong>Context: </strong>Boron-doped iron clusters are extensively studied for their potential in materials science. Despite several quantum calculations with DFT and MRCI methods, a comprehensive understanding of the geometric and electronic structures of small FeB_n^-/0/+ clusters (n = 1-3) is still lacking. This work provides new insights into ground and low-lying excited states, detachment energies, and ionization energies of these clusters using DFT and multireference CASPT2, RASPT2, and DMRG-CASPT2 computational methods. Key findings reveal ³Σ^-, ⁴Σ^-, and ³Σ^- as ground states for FeB^-/0/+, and cyclic-FeB₂^-/0/+ isomers (⁴B₂, ³B₂, ⁴B₁) as the most stable for FeB₂^-/0/+ clusters. For FeB₃ clusters, anionic species have a tetrahedral geometry, while neutral and cationic species favor rhombic structures. Detachment energies of the anionic ground states increase progressively from FeB^- to cyclic-FeB₂^-, and further to the tetrahedral-FeB₃^- isomer, which correlates with the number of boron atoms bonded to the iron atom. The vibrational progression in transitions within tetrahedral-FeB₃^-/0 is more prominent than in FeB^-/0 clusters and cyclic-FeB₂^-/0 isomers. The ionization energies of neutral ground states rise from FeB clusters to rhombic-FeB₃ and cyclic-FeB₂ isomers.</p><p><strong>Methods: </strong>The geometry optimization and vibrational frequency calculations for the electronic states of FeB₂^-/0/+ and FeB₃^-/0/+ clusters were conducted using density functional theory (DFT) with the BP86 and MN15 functionals and the def2-QZVP basis set, implemented in ORCA 5.0. Franck-Condon factor simulations were performed using the ezSpectra suite, based on DFT-derived geometries and vibrational normal modes. Multireference RASPT2 and CASPT2 calculations utilized OpenMolcas, while DMRG-CASPT2 calculations employed ChemPS2 interfaced to OpenMolcas. The aug-cc-pwCVQZ-DK basis set was applied to iron, and aug-cc-pVQZ-DK to boron. The 1 s, 2 s, and 2p orbitals of iron and the 1 s orbital of boron were frozen in the second-order perturbation calculations. IPEA and imaginary shift parameters were set to 0.25 and 0.10, respectively. To achieve high accuracy, the DMRG-CASPT2 active spaces were expanded to 22 orbitals for FeB^-/0/+ and FeB₂^-/0/+, and 23 orbitals for FeB₃^-/0/+.</p>","PeriodicalId":651,"journal":{"name":"Journal of Molecular Modeling","volume":"31 7","pages":"199"},"PeriodicalIF":2.1,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}