Pub Date : 2025-11-29DOI: 10.1016/j.comptc.2025.115604
Marco Aurélio Cebim
This study introduces a novel framework for classifying chemical elements grounded in the correlation of energetic parameters associated with chemical bonding in elemental substances under standard conditions. The enthalpy of formation of gaseous atoms () and the bond dissociation energy () are employed to define a dimensionless quantity (). This parameter reflects the tendency of elements to form simple neutral molecules of the type . Representative values and other relevant properties are discussed throughout the manuscript. The chemical elements were represented in a scatter plot of as a function of , in which a wide separation between metals and nonmetals (and noble gases) is observed, with metalloids distributed between these two types of elements. Finally, a scatter plot is proposed relating the parameter and electronegativity, in which the chemical elements appear grouped as metals, metalloids, and nonmetals without apparent ambiguity.
{"title":"Correlation between the enthalpy of formation of gaseous atoms from elemental substances and the bond dissociation energy of homonuclear diatomic molecules: Exploratory perspectives on alternative classification schemes for chemical elements","authors":"Marco Aurélio Cebim","doi":"10.1016/j.comptc.2025.115604","DOIUrl":"10.1016/j.comptc.2025.115604","url":null,"abstract":"<div><div>This study introduces a novel framework for classifying chemical elements grounded in the correlation of energetic parameters associated with chemical bonding in elemental substances under standard conditions. The enthalpy of formation of gaseous atoms (<span><math><msub><mo>∆</mo><mi>f</mi></msub><msup><mi>H</mi><mi>o</mi></msup></math></span>) and the bond dissociation energy (<span><math><mi>BDE</mi></math></span>) are employed to define a dimensionless quantity (<span><math><mi>β</mi><mo>=</mo><msub><mo>∆</mo><mi>f</mi></msub><msup><mi>H</mi><mi>o</mi></msup><mo>/</mo><mi>BDE</mi></math></span>). This parameter reflects the tendency of elements to form simple neutral molecules of the type <span><math><msub><mi>X</mi><mi>n</mi></msub></math></span>. Representative <span><math><mi>β</mi></math></span> values and other relevant properties are discussed throughout the manuscript. The chemical elements were represented in a scatter plot of <span><math><msub><mo>∆</mo><mi>f</mi></msub><msup><mi>H</mi><mi>o</mi></msup></math></span> as a function of <span><math><mi>BDE</mi></math></span>, in which a wide separation between metals and nonmetals (and noble gases) is observed, with metalloids distributed between these two types of elements. Finally, a scatter plot is proposed relating the <span><math><mi>β</mi></math></span> parameter and electronegativity, in which the chemical elements appear grouped as metals, metalloids, and nonmetals without apparent ambiguity.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115604"},"PeriodicalIF":3.0,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691182","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}
Pub Date : 2025-11-29DOI: 10.1016/j.comptc.2025.115603
Jiaying Shang, Minghui Kong, Qiankun Zhang
As HfO₂’s use in ferroelectrics has grown revolutionarily lately, and common oxygen vacancies in it have unclear polarization switching regulation mechanisms, investigating how their concentration and position affect HfO₂’s polarization switching matters for ferroelectric development. Based on density functional theory, a series of HfO2 structures with different concentrations and positions of oxygen vacancies are constructed. The calculation results of formation energy show that the difficulty of forming oxygen vacancies is significantly related to the coordination environment and concentration. Through the CI-NEB method, the energy barrier is calculated, revealing that as the concentration of O vacancies increases, the entire energy barrier will gradually decrease. The energy barrier of HfO2-V4-I can be reduced to 0.67 eV. This study clarifies the regulatory rules of oxygen vacancies on the polarization switching of HfO2, providing a key theoretical basis for optimizing the performance of ferroelectric devices through defect engineering.
{"title":"A systematic DFT study on the effects of oxygen vacancy concentration and site-dependence on polarization switching in HfO2","authors":"Jiaying Shang, Minghui Kong, Qiankun Zhang","doi":"10.1016/j.comptc.2025.115603","DOIUrl":"10.1016/j.comptc.2025.115603","url":null,"abstract":"<div><div>As HfO₂’s use in ferroelectrics has grown revolutionarily lately, and common oxygen vacancies in it have unclear polarization switching regulation mechanisms, investigating how their concentration and position affect HfO₂’s polarization switching matters for ferroelectric development. Based on density functional theory, a series of HfO<sub>2</sub> structures with different concentrations and positions of oxygen vacancies are constructed. The calculation results of formation energy show that the difficulty of forming oxygen vacancies is significantly related to the coordination environment and concentration. Through the CI-NEB method, the energy barrier is calculated, revealing that as the concentration of O vacancies increases, the entire energy barrier will gradually decrease. The energy barrier of HfO<sub>2</sub>-V4-I can be reduced to 0.67 eV. This study clarifies the regulatory rules of oxygen vacancies on the polarization switching of HfO<sub>2</sub>, providing a key theoretical basis for optimizing the performance of ferroelectric devices through defect engineering.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115603"},"PeriodicalIF":3.0,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691184","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}
Pub Date : 2025-11-29DOI: 10.1016/j.comptc.2025.115616
Joel Leitão Nascimento, Daniel Moura, Edivania Santana, Vitor H. Menezes da Silva, Tiago Vinicius Alves
A comprehensive understanding of how water vapor affects the OH-addition to furan is essential, as these reactions constitute one of the primary atmospheric degradation pathways. The ability of water to form highly stable two- and three-body complexes creates the possibility for modulating the reaction mechanism for furan degradation in the gas-phase, thus motivating us to carry out a systematic investigation of its elusive catalytic role on this process. To this end, Density Functional Theory (DFT) calculations have been performed, providing thirteen distinct water-assisted pathways computed. In addition, the canonical variational transition state theory with small-curvature tunneling (CVT/SCT), combined with the pre-equilibrium model (PEM), have been employed in order to compute termolecular and effective rate constants at different relative humidities. Overall, the results indicate that the catalytic effect of water, including contributions from H-abstraction is negligible, although its occurrence cannot be entirely ruled out under high-temperature conditions. Specifically, under tropospheric conditions, water-mediated OH-addition pathways are kinetically disfavored by more than three orders of magnitude compared to the gas-phase mechanism.
{"title":"Exploring the elusive catalytic role of water in the OH ＋ furan reaction","authors":"Joel Leitão Nascimento, Daniel Moura, Edivania Santana, Vitor H. Menezes da Silva, Tiago Vinicius Alves","doi":"10.1016/j.comptc.2025.115616","DOIUrl":"10.1016/j.comptc.2025.115616","url":null,"abstract":"<div><div>A comprehensive understanding of how water vapor affects the OH-addition to furan is essential, as these reactions constitute one of the primary atmospheric degradation pathways. The ability of water to form highly stable two- and three-body complexes creates the possibility for modulating the reaction mechanism for furan degradation in the gas-phase, thus motivating us to carry out a systematic investigation of its elusive catalytic role on this process. To this end, Density Functional Theory (DFT) calculations have been performed, providing thirteen distinct water-assisted pathways computed. In addition, the canonical variational transition state theory with small-curvature tunneling (CVT/SCT), combined with the pre-equilibrium model (PEM), have been employed in order to compute termolecular and effective rate constants at different relative humidities. Overall, the results indicate that the catalytic effect of water, including contributions from H-abstraction is negligible, although its occurrence cannot be entirely ruled out under high-temperature conditions. Specifically, under tropospheric conditions, water-mediated OH-addition pathways are kinetically disfavored by more than three orders of magnitude compared to the gas-phase mechanism.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115616"},"PeriodicalIF":3.0,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691220","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}
Deep eutectic solvents (DESs) based on decanoic acid have emerged as promising green solvents due to their biodegradability and tunable properties. However, their behavior in aqueous environments remains insufficiently understood, limiting their broader application in chemical processes.
Methods
COSMO-RS (Conductor-like Screening Model for Real Solvents) calculations, combined with molecular dynamics simulations, were employed to systematically investigate the intermolecular interactions, miscibility, and structural organization of decanoic acid–based deep eutectic solvents in the presence of water. A detailed analysis of thermodynamic descriptors, hydrogen-bonding patterns, and spatial distribution functions was conducted to elucidate the solvent behavior and molecular-level interaction mechanisms governing water – DES systems.
Significant findings
The results reveal non-ideal mixing behavior and highlight the critical role of hydrogen bonding and hydrophobic interactions in governing aqueous phase behavior. COSMO-RS predicted partial miscibility trends consistent with simulation results. These insights offer a theoretical foundation for designing water-compatible DES systems for sustainable chemical applications. The interactions between DES components and water molecules were systematically analyzed to understand the solvation effects, hydrogen bonding networks, and structural properties in varying hydration levels. This study examines key properties such as the combined distribution function, spatial distribution function, intermolecular hydrogen bond network, interaction energy, species orientation, density, and self-diffusion coefficients (Dself). Molecular dynamics simulations reveal that increasing the water mass fraction up to 50% weakens the interaction between DES components, significantly impacting their stability and solvation characteristics. These findings provide valuable insights into the behavior of hydrophobic DESs, contributing to their potential applications in pharmaceutical and green chemistry fields.
{"title":"Understanding the aqueous behavior of decanoic acid-based deep eutectic solvents via COSMO-RS and molecular simulations","authors":"Samaneh Barani Pour , Behie Amirian , Leyla Bagheri , Jaber Jahanbin Sardroodi","doi":"10.1016/j.comptc.2025.115608","DOIUrl":"10.1016/j.comptc.2025.115608","url":null,"abstract":"<div><h3>Background</h3><div>Deep eutectic solvents (DESs) based on decanoic acid have emerged as promising green solvents due to their biodegradability and tunable properties. However, their behavior in aqueous environments remains insufficiently understood, limiting their broader application in chemical processes.</div></div><div><h3>Methods</h3><div>COSMO-RS (Conductor-like Screening Model for Real Solvents) calculations, combined with molecular dynamics simulations, were employed to systematically investigate the intermolecular interactions, miscibility, and structural organization of decanoic acid–based deep eutectic solvents in the presence of water. A detailed analysis of thermodynamic descriptors, hydrogen-bonding patterns, and spatial distribution functions was conducted to elucidate the solvent behavior and molecular-level interaction mechanisms governing water – DES systems.</div></div><div><h3>Significant findings</h3><div>The results reveal non-ideal mixing behavior and highlight the critical role of hydrogen bonding and hydrophobic interactions in governing aqueous phase behavior. COSMO-RS predicted partial miscibility trends consistent with simulation results. These insights offer a theoretical foundation for designing water-compatible DES systems for sustainable chemical applications. The interactions between DES components and water molecules were systematically analyzed to understand the solvation effects, hydrogen bonding networks, and structural properties in varying hydration levels. This study examines key properties such as the combined distribution function, spatial distribution function, intermolecular hydrogen bond network, interaction energy, species orientation, density, and self-diffusion coefficients (D<sub>self</sub>). Molecular dynamics simulations reveal that increasing the water mass fraction up to 50% weakens the interaction between DES components, significantly impacting their stability and solvation characteristics. These findings provide valuable insights into the behavior of hydrophobic DESs, contributing to their potential applications in pharmaceutical and green chemistry fields.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115608"},"PeriodicalIF":3.0,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691227","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}
This study investigates uncatalyzed and ruthenium (II)-catalyzed (3 + 2) cycloaddition (32CA) reactions between nitrile N-oxide and internal thioalkyne using the M06-2×-D3 level of theory.The def2-TZVPD basis set was employed for Ru atoms, and 6-311G(d,p) for all others. Uncatalyzed pathways toward 1,4- and 1,5-isoxazole regioisomers exhibited comparable Gibbs free energies (−65.7 and − 60.3 kcal·mol−1), indicating minimal regioselectivity, consistent with experimental observations. Ru(II) catalysis significantly enhanced regioselectivity by modulating electronic structures and bonding evolution. ELF and CDFT analyses confirmed the zwitterionic character of nitrile N-oxide and electron density transfer from thioalkynes. GEDT values revealed low-polarity thermal pathways versus more polar Ru-catalyzed ones.BET supported a stepwise mechanism in uncatalyzed reactions and catalyst-dependent modulation in Ru(II)-mediated systems.Molecular docking against MCF-7 protein(PDB: 3ERT)indicated moderate binding affinities (−9.3 and − 9.7 kcal·mol−1) compared to the reference ligand (−13.1 kcal·mol−1). ADMET, toxicity,MD simulations, and PASS predictions suggest favorable pharmacokinetic and anticancer potential for both regioisomers,underscoring their mechanistic and biological relevance.
{"title":"Mechanistic and Regioselective insights into thermal and ruthenium (II)-catalyzed (3 + 2) cycloadditions of nitrile N-oxide with internal thioalkyne: a combined on Isoxazole derivatives, molecular docking, ADMET approach, MD and PASS simulations from the MEDT perspective","authors":"Raghad Mowafak Al-Mokhtar , Haydar Mohammad-Salim , Muheb Algso","doi":"10.1016/j.comptc.2025.115601","DOIUrl":"10.1016/j.comptc.2025.115601","url":null,"abstract":"<div><div>This study investigates uncatalyzed and ruthenium (II)-catalyzed (3 + 2) cycloaddition (32CA) reactions between nitrile N-oxide and internal thioalkyne using the M06-2×-D3 level of theory.The def2-TZVPD basis set was employed for Ru atoms, and 6-311G(d,p) for all others. Uncatalyzed pathways toward 1,4- and 1,5-isoxazole regioisomers exhibited comparable Gibbs free energies (−65.7 and − 60.3 kcal·mol<sup>−1</sup>), indicating minimal regioselectivity, consistent with experimental observations. Ru(II) catalysis significantly enhanced regioselectivity by modulating electronic structures and bonding evolution. ELF and CDFT analyses confirmed the zwitterionic character of nitrile N-oxide and electron density transfer from thioalkynes. GEDT values revealed low-polarity thermal pathways versus more polar Ru-catalyzed ones.BET supported a stepwise mechanism in uncatalyzed reactions and catalyst-dependent modulation in Ru(II)-mediated systems.Molecular docking against MCF-7 protein(PDB: <span><span>3ERT</span><svg><path></path></svg></span>)indicated moderate binding affinities (−9.3 and − 9.7 kcal·mol<sup>−1</sup>) compared to the reference ligand (−13.1 kcal·mol<sup>−1</sup>). ADMET, toxicity,MD simulations, and PASS predictions suggest favorable pharmacokinetic and anticancer potential for both regioisomers,underscoring their mechanistic and biological relevance.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115601"},"PeriodicalIF":3.0,"publicationDate":"2025-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691222","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}
Pub Date : 2025-11-28DOI: 10.1016/j.comptc.2025.115618
Qihui Bai , Xihua Zhou , Gang Bai , Fei Gao
To investigate the influence of CO2 and N2 on the oxidative reaction of coal, a combined method of molecular dynamics and quantum chemical calculation was applied to infer the reaction paths of side chain and bridge bond active groups in coal with ·OH and O2 during low-temperature oxidation. The activation stages of chemical reactions involving active groups were divided. The inerting mechanism of CO2 and N2 on the oxidative reaction of active groups in coal was revealed from the physical adsorption, chemical adsorption, and chemical reaction stages of coal oxidation. The results showed that before CO2 and N2 interacted with the active groups, CO2 effectively hindered the physical and chemical adsorption processes of the active groups on O2 by virtue of its strongly competitive adsorption characteristics, while having no significant effect on ·OH. In contrast, N2 showed no substantial interference with either the physical or chemical adsorption stages of the active groups. After van der Waals interactions with the active groups, both CO2 and N2 could inert the chemical adsorption of the active groups with ·OH and O2, and the inerting effect of CO2 on the chemical adsorption of the active groups was approximately more than twice that of N2. The chemical reactions of active groups could be subdivided into three activation stages. Stage I was the activation of cyclic chain reactions between active groups and free radicals under room-temperature conditions. Stages II and III were the activation of composite reactions between active groups and O2 at 30–70 °C and 70–200 °C, respectively. The influence of CO2 on the activation stages I, II, and III showed a change rule of “inhibition-promotion-inhibition,” while N2 had a significant promotional effect on the three activation stages. The inerting effect of CO2 on the chemical reactions of active groups consistently outperformed that of N2 throughout the entire low-temperature oxidation process. The study results will offer an important basis for refining the fundamental theory of fire prevention and control technology using inert gases in coal mines.
{"title":"Inerting mechanism of CO2 and N2 on the oxidative reaction of active groups in coal","authors":"Qihui Bai , Xihua Zhou , Gang Bai , Fei Gao","doi":"10.1016/j.comptc.2025.115618","DOIUrl":"10.1016/j.comptc.2025.115618","url":null,"abstract":"<div><div>To investigate the influence of CO<sub>2</sub> and N<sub>2</sub> on the oxidative reaction of coal, a combined method of molecular dynamics and quantum chemical calculation was applied to infer the reaction paths of side chain and bridge bond active groups in coal with ·OH and O<sub>2</sub> during low-temperature oxidation. The activation stages of chemical reactions involving active groups were divided. The inerting mechanism of CO<sub>2</sub> and N<sub>2</sub> on the oxidative reaction of active groups in coal was revealed from the physical adsorption, chemical adsorption, and chemical reaction stages of coal oxidation. The results showed that before CO<sub>2</sub> and N<sub>2</sub> interacted with the active groups, CO<sub>2</sub> effectively hindered the physical and chemical adsorption processes of the active groups on O<sub>2</sub> by virtue of its strongly competitive adsorption characteristics, while having no significant effect on ·OH. In contrast, N<sub>2</sub> showed no substantial interference with either the physical or chemical adsorption stages of the active groups. After van der Waals interactions with the active groups, both CO<sub>2</sub> and N<sub>2</sub> could inert the chemical adsorption of the active groups with ·OH and O<sub>2</sub>, and the inerting effect of CO<sub>2</sub> on the chemical adsorption of the active groups was approximately more than twice that of N<sub>2</sub>. The chemical reactions of active groups could be subdivided into three activation stages. Stage I was the activation of cyclic chain reactions between active groups and free radicals under room-temperature conditions. Stages II and III were the activation of composite reactions between active groups and O<sub>2</sub> at 30–70 °C and 70–200 °C, respectively. The influence of CO<sub>2</sub> on the activation stages I, II, and III showed a change rule of “inhibition-promotion-inhibition,” while N<sub>2</sub> had a significant promotional effect on the three activation stages. The inerting effect of CO<sub>2</sub> on the chemical reactions of active groups consistently outperformed that of N<sub>2</sub> throughout the entire low-temperature oxidation process. The study results will offer an important basis for refining the fundamental theory of fire prevention and control technology using inert gases in coal mines.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115618"},"PeriodicalIF":3.0,"publicationDate":"2025-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691179","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}
Pub Date : 2025-11-28DOI: 10.1016/j.comptc.2025.115617
To Toan Thang , Nguyen Hoang Linh , Dinh The Hung , Do Van Truong
The growing demand for efficient thermoelectric and optoelectronic devices has driven the search for two-dimensional (2D) semiconductors with superior transport and tunable electronic structures. Here, we perform first-principles calculations to explore the structural stability, mechanical anisotropy, and strain-dependent electronic, optical, and thermoelectric properties of the AuS monolayer. The cohesive energy (3.52 eV/atom), phonon spectra, and ab initio molecular dynamics confirm its strong thermodynamic stability. Uniaxial tension reveals pronounced anisotropy with ultimate strengths of 14.62 GPa (εxx = 0.28) and 16.76 GPa (εyy = 0.34). Unstrained AuS shows an indirect HSE band gap of 2.15 eV, decreasing by 44 % under x-strain, accompanied by red-shifted and enhanced visible–IR absorption (up to 10 times). A favorable electron–hole mass ratio (D = 0.54) enables a peak ZT of 0.71 and a Seebeck coefficient of 2.2 mV/K. These strain-adaptive multifunctional properties make AuS a promising 2D semiconductor for flexible energy-conversion applications.
{"title":"The AuS monolayer: mechanical anisotropy, strain-tunable optoelectronic properties and high thermoelectric efficiency","authors":"To Toan Thang , Nguyen Hoang Linh , Dinh The Hung , Do Van Truong","doi":"10.1016/j.comptc.2025.115617","DOIUrl":"10.1016/j.comptc.2025.115617","url":null,"abstract":"<div><div>The growing demand for efficient thermoelectric and optoelectronic devices has driven the search for two-dimensional (2D) semiconductors with superior transport and tunable electronic structures. Here, we perform first-principles calculations to explore the structural stability, mechanical anisotropy, and strain-dependent electronic, optical, and thermoelectric properties of the AuS monolayer. The cohesive energy (3.52 eV/atom), phonon spectra, and ab initio molecular dynamics confirm its strong thermodynamic stability. Uniaxial tension reveals pronounced anisotropy with ultimate strengths of 14.62 GPa (<em>ε</em><sub><em>xx</em></sub> = 0.28) and 16.76 GPa (<em>ε</em><sub><em>yy</em></sub> = 0.34). Unstrained AuS shows an indirect HSE band gap of 2.15 eV, decreasing by 44 % under <em>x</em>-strain, accompanied by red-shifted and enhanced visible–IR absorption (up to 10 times). A favorable electron–hole mass ratio (<em>D</em> = 0.54) enables a peak <em>ZT</em> of 0.71 and a Seebeck coefficient of 2.2 mV/K. These strain-adaptive multifunctional properties make AuS a promising 2D semiconductor for flexible energy-conversion applications.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115617"},"PeriodicalIF":3.0,"publicationDate":"2025-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691228","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}
Pub Date : 2025-11-28DOI: 10.1016/j.comptc.2025.115620
Irina I. Piyanzina , Zarina I. Minnegulova , Regina M. Burganova , Oleg V. Nedopekin , Igor V. Yanilkin , Vasiliy S. Stolyarov , Amir I. Gumarov
Low-impurity ferromagnetism remains a challenging problem without a unified theoretical description. We systematically investigate Pd alloys (Me = Mn, Fe, Co, Ni) using first-principles DFT across impurity concentrations from 1 to 100 at.. Our refined methodology accurately predicts magnetic and electronic properties, tracing the transition from isolated magnetic impurities to bulk ferromagnetism. We identify critical concentrations where spontaneous magnetization appears and observe a sharp onset of magnetic ordering at dilute limits. For Mn- and Ni-doped systems, the critical concentration is found near 3 at.%, corresponding to ferrimagnetic ordering in both cases. In contrast, Fe- and Co-doped alloys exhibit no distinct critical threshold within the studied range, suggesting that the onset occurs below 1 at.%. Pd-Fe displays ferrimagnetic behavior, while Pd-Co is in ferromagnetic state. Overall, the maximal magnetic moments per impurity are similar for all series, lying within . Moreover, electronic structure analysis, including atomic, spin-, and orbital-resolved density of states, clarifies the formation and spatial evolution of magnetic clusters. This work provides new theoretical insights into the microscopic mechanisms underlying low-impurity ferromagnetism in Pd-based alloys.
{"title":"Effect of 3d transition metal doping (Mn, Fe, Co, Ni) on the electronic and magnetic properties of Pd alloys at low impurity concentrations: An Ab initio study","authors":"Irina I. Piyanzina , Zarina I. Minnegulova , Regina M. Burganova , Oleg V. Nedopekin , Igor V. Yanilkin , Vasiliy S. Stolyarov , Amir I. Gumarov","doi":"10.1016/j.comptc.2025.115620","DOIUrl":"10.1016/j.comptc.2025.115620","url":null,"abstract":"<div><div>Low-impurity ferromagnetism remains a challenging problem without a unified theoretical description. We systematically investigate Pd<span><math><mrow><msub><mrow></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub><mi>M</mi><msub><mrow><mi>e</mi></mrow><mrow><mi>x</mi></mrow></msub></mrow></math></span> alloys (Me = Mn, Fe, Co, Ni) using first-principles DFT across impurity concentrations from 1 to 100<!--> <!-->at.<span><math><mtext>%</mtext></math></span>. Our refined methodology accurately predicts magnetic and electronic properties, tracing the transition from isolated magnetic impurities to bulk ferromagnetism. We identify critical concentrations where spontaneous magnetization appears and observe a sharp onset of magnetic ordering at dilute limits. For Mn- and Ni-doped systems, the critical concentration is found near 3<!--> <!-->at.%, corresponding to ferrimagnetic ordering in both cases. In contrast, Fe- and Co-doped alloys exhibit no distinct critical threshold within the studied range, suggesting that the onset occurs below 1<!--> <!-->at.%. Pd-Fe displays ferrimagnetic behavior, while Pd-Co is in ferromagnetic state. Overall, the maximal magnetic moments per impurity are similar for all series, lying within <span><math><mrow><mn>13</mn><mo>−</mo><mn>15</mn><msub><mrow><mi>μ</mi></mrow><mrow><mi>B</mi></mrow></msub></mrow></math></span>. Moreover, electronic structure analysis, including atomic, spin-, and orbital-resolved density of states, clarifies the formation and spatial evolution of magnetic clusters. This work provides new theoretical insights into the microscopic mechanisms underlying low-impurity ferromagnetism in Pd-based alloys.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115620"},"PeriodicalIF":3.0,"publicationDate":"2025-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691183","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}
Pub Date : 2025-11-27DOI: 10.1016/j.comptc.2025.115606
Xinmeng Zhao , Yuke Zuo , Wanting Wang , Maoxia He , Ju Xie
Dioxins, as a class of persistent organic pollutants (POPs), pose a great danger to human health and the environment. This study proposed the use of pillar[6]arene (P6) and thiapillar[6]arene analogues (P6Ss), namely P6S, P6SO, and P6SO2, as a kind of high-efficient adsorbent material for dioxin pollutants. P6 and P6Ss as the host molecules, polychlorinated dibenzo-p-dioxins (pCDD) as the guest molecules, and their 1:1 inclusion complexes have been studied systematically using density functional theory (DFT) calculations at the ωB97XD/6-311G(d,p) level of theory. The geometrical structures and electronic structures of P6 and P6Ss were significantly diversified by different bridging groups between two aromatic rings. Based on the spatial matching of molecular cavities and the complementarity of electronic properties, P6 and P6Ss were favorable for the formation of 1:1 inclusion complexes with dioxin molecules, mainly driven by π–π stacking, H-bonding, and van der Waals interactions. P6 and P6SO2 exhibited strong host–guest interactions with TCDD and H6CDD, respectively. Subsequently, molecular dynamics (MD) simulations showed that both crystalline and non-crystalline aggregates of P6 and P6Ss were able to capture pCDDs with a 1:1 stoichiometric ratio and maintain the dynamic equilibrium state. These findings indicated that pillar[n]arene analogues are expected to be a new solution for dioxin control.
{"title":"Mechanism study on quantitative adsorption of dioxin-like pollutants by pillar[6]arene and thiapillar[6]arenes","authors":"Xinmeng Zhao , Yuke Zuo , Wanting Wang , Maoxia He , Ju Xie","doi":"10.1016/j.comptc.2025.115606","DOIUrl":"10.1016/j.comptc.2025.115606","url":null,"abstract":"<div><div>Dioxins, as a class of persistent organic pollutants (POPs), pose a great danger to human health and the environment. This study proposed the use of pillar[6]arene (P6) and thiapillar[6]arene analogues (P6Ss), namely P6S, P6SO, and P6SO<sub>2</sub>, as a kind of high-efficient adsorbent material for dioxin pollutants. P6 and P6Ss as the host molecules, polychlorinated dibenzo-p-dioxins (pCDD) as the guest molecules, and their 1:1 inclusion complexes have been studied systematically using density functional theory (DFT) calculations at the ωB97XD/6-311G(d,p) level of theory. The geometrical structures and electronic structures of P6 and P6Ss were significantly diversified by different bridging groups between two aromatic rings. Based on the spatial matching of molecular cavities and the complementarity of electronic properties, P6 and P6Ss were favorable for the formation of 1:1 inclusion complexes with dioxin molecules, mainly driven by π–π stacking, H-bonding, and van der Waals interactions. P6 and P6SO<sub>2</sub> exhibited strong host–guest interactions with TCDD and H<sub>6</sub>CDD, respectively. Subsequently, molecular dynamics (MD) simulations showed that both crystalline and non-crystalline aggregates of P6 and P6Ss were able to capture pCDDs with a 1:1 stoichiometric ratio and maintain the dynamic equilibrium state. These findings indicated that pillar[<em>n</em>]arene analogues are expected to be a new solution for dioxin control.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115606"},"PeriodicalIF":3.0,"publicationDate":"2025-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691229","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}
Pub Date : 2025-11-27DOI: 10.1016/j.comptc.2025.115615
Shuying Wang
The reliable operation of oil-immersed transformers is essential for power system stability, where dissolved gas analysis (DGA) has been established as a fundamental diagnostic technique for early fault detection through gas monitoring. This investigation utilizes first-principles calculations to comprehensively evaluate the gas sensing capabilities of a Pd-doped GeTe (Pd-GeTe) monolayer for detecting three dominant dissolved gases—H2, CO, and C2H2—in transformer oil. Our study explores the structural and electronic properties of the doped material, revealing that Pd substitution at Te sites is thermodynamically favorable with a formation energy of −0.65 eV. The adsorption strength hierarchy (CO > C2H2 > H2) correlates directly with calculated adsorption energies of −0.88 eV, −0.49 eV, and − 0.11 eV, respectively, supported by distinct charge transfer values and orbital hybridization patterns. Remarkably, the material demonstrates exceptional sensing responses of −82.66 %, −99.68 %, and − 99.07 % toward H2, CO and C2H2, respectively. Furthermore, recovery time analysis reveals the monolayer's practical reusability. These findings establish Pd-GeTe as a highly promising and reversible sensing platform for DGA applications, providing atomic-level insights into gas-sensing mechanisms and advancing the development of high-performance diagnostic systems for power transformer monitoring.
{"title":"Pd-doped GeTe monolayer as a promising gas scavenger upon H2, CO and C2H2 in oil-immersed transformers: a first-principles study","authors":"Shuying Wang","doi":"10.1016/j.comptc.2025.115615","DOIUrl":"10.1016/j.comptc.2025.115615","url":null,"abstract":"<div><div>The reliable operation of oil-immersed transformers is essential for power system stability, where dissolved gas analysis (DGA) has been established as a fundamental diagnostic technique for early fault detection through gas monitoring. This investigation utilizes first-principles calculations to comprehensively evaluate the gas sensing capabilities of a Pd-doped GeTe (Pd-GeTe) monolayer for detecting three dominant dissolved gases—H<sub>2</sub>, CO, and C<sub>2</sub>H<sub>2</sub>—in transformer oil. Our study explores the structural and electronic properties of the doped material, revealing that Pd substitution at Te sites is thermodynamically favorable with a formation energy of −0.65 eV. The adsorption strength hierarchy (CO > C<sub>2</sub>H<sub>2</sub> > H<sub>2</sub>) correlates directly with calculated adsorption energies of −0.88 eV, −0.49 eV, and − 0.11 eV, respectively, supported by distinct charge transfer values and orbital hybridization patterns. Remarkably, the material demonstrates exceptional sensing responses of −82.66 %, −99.68 %, and − 99.07 % toward H<sub>2</sub>, CO and C<sub>2</sub>H<sub>2</sub>, respectively. Furthermore, recovery time analysis reveals the monolayer's practical reusability. These findings establish Pd-GeTe as a highly promising and reversible sensing platform for DGA applications, providing atomic-level insights into gas-sensing mechanisms and advancing the development of high-performance diagnostic systems for power transformer monitoring.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1256 ","pages":"Article 115615"},"PeriodicalIF":3.0,"publicationDate":"2025-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145691181","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}
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