Theoretical modeling using DFT and TDDFT methods explored optimal donor groups for the organic dye “3-(5-(4-(Diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic Acid”. Seven different moieties and their derivatives mostly used as donors as obtained from the literature (methylamine, benzene, fluorene, carbazole, phenylaniline, indolizine and pyrrolizine) were investigated, and our calculations highlighted indolizine and pyrrolizine derivatives as the most effective donors among those studied. The strong push pull effect of such derivatives of indolizine and pyrrolizine groups played a role in enhancing the efficiency of the dye sensitizers.
{"title":"Optimal donor groups for novel organic dye “3-(5-(4-(diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid” in the context of N‑type dye-sensitized solar cells: A theoretical investigation","authors":"Preeti Nanda Sahu, Anjali Devi Vasarla, Rajesh Kumar Kumili, Anik Sen","doi":"10.1016/j.comptc.2024.114901","DOIUrl":"10.1016/j.comptc.2024.114901","url":null,"abstract":"<div><div>Theoretical modeling using DFT and TDDFT methods explored optimal donor groups for the organic dye “3-(5-(4-(Diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic Acid”. Seven different moieties and their derivatives mostly used as donors as obtained from the literature (methylamine, benzene, fluorene, carbazole, phenylaniline, indolizine and pyrrolizine) were investigated, and our calculations highlighted indolizine and pyrrolizine derivatives as the most effective donors among those studied. The strong push pull effect of such derivatives of indolizine and pyrrolizine groups played a role in enhancing the efficiency of the dye sensitizers.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114901"},"PeriodicalIF":3.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422839","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 : 2024-09-30DOI: 10.1016/j.comptc.2024.114902
Saba Saleem, Nawaz Muhammad, G. Murtaza, Ahmad Ayyaz, Maha Naeem, Ahmad Usman, Urwa-tul Aysha, Maryam Touqir
The structural, electronic, elastic, magnetic, and thermoelectric characteristics of three novel Ta-based half-Heusler alloys, CsTaC, CsTaSi, and CsTaGe, have been investigated using the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within the density functional theory (DFT). The volume-optimization graphs show that all compounds are stable in the ferromagnetic (FM) phase. Half-Metallicity of these compounds is confirmed by the density of states (DOS) and band structures. The total magnetic moment for CsTaC is 6 B, and for CsTaX (X = Si, Ge) is 2 B. The negative pd exchange energy and exchange constants confirm ferromagnetism. The values of Pugh’s ratio (B/G) and Poisson’s ratio (v) reveal that CsTaC is ductile and CsTaX (Si, Ge) is brittle. The thermoelectric response is estimated using the BoltzTraP code, demonstrating that at room temperature, maximum ZT values for CaTaC, CsTaSi, and CsTaGe are 0.99, 0.97, and 0.90, respectively. Consequently, CsTaX (X = C, Si, and Ge) are suitable candidates for spintronic and thermoelectric technologies.
{"title":"DFT study of structural, electronic, magnetic, elastic, and thermoelectric properties of Ta-based half-Heusler alloys CsTaX (X = C, Si, and Ge) for spintronics and thermoelectric technologies","authors":"Saba Saleem, Nawaz Muhammad, G. Murtaza, Ahmad Ayyaz, Maha Naeem, Ahmad Usman, Urwa-tul Aysha, Maryam Touqir","doi":"10.1016/j.comptc.2024.114902","DOIUrl":"10.1016/j.comptc.2024.114902","url":null,"abstract":"<div><div>The structural, electronic, elastic, magnetic, and thermoelectric characteristics of three novel Ta-based half-Heusler alloys, CsTaC, CsTaSi, and CsTaGe, have been investigated using the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within the density functional theory (DFT). The volume-optimization graphs show that all compounds are stable in the ferromagnetic (FM) phase. Half-Metallicity of these compounds is confirmed by the density of states (DOS) and band structures. The total magnetic moment for CsTaC is 6 <span><math><mi>μ</mi></math></span><sub>B,</sub> and for CsTaX (X = Si, Ge) is 2 <span><math><mi>μ</mi></math></span><sub>B</sub>. The negative pd exchange energy and exchange constants confirm ferromagnetism. The values of Pugh’s ratio (B/G) and Poisson’s ratio (v) reveal that CsTaC is ductile and CsTaX (Si, Ge) is brittle. The thermoelectric response is estimated using the BoltzTraP code, demonstrating that at room temperature, maximum <em>ZT</em> values for CaTaC, CsTaSi, and CsTaGe are 0.99, 0.97, and 0.90, respectively. Consequently, CsTaX (X = C, Si, and Ge) are suitable candidates for spintronic and thermoelectric technologies.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114902"},"PeriodicalIF":3.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422840","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 : 2024-09-30DOI: 10.1016/j.comptc.2024.114900
Yong Zhang , Zheng Mei , Ling-Chen Zhou , Jing Ye , Fang-Chao Hou , Bo-Cong Chen , Hao-Long Su , Jing Sun , Liang Song
In this study, the ReaxFF-lg reactive force field was verified and employed to simulate the thermal decomposition of nitroglycerin (NG) and 1,2,4-butanetriol trinitrate (BTTN) at various temperatures (1500–3000 K), elucidating the detailed mechanisms of initial changes, intermediate products, and final product reactions for both energetic materials. The results indicate that the initial reactions of NG and BTTN are similar, and the primary reactions involve the cleavage of the O-NO2 bond and the dissociation of the CC bond. At 1500 K, the breakage of O-NO2 bonds becomes the dominant reaction. As the temperature increases, in addition to the removal of NO2, the breakage of CC chains is observed above 2000 K. The formation of intermediates NO2, HNO2, NO, and CH2O accelerates the chemical reaction. The proportions of CO2 and H2O in the final products of BTTN change significantly with temperature.
本研究验证了 ReaxFF-lg 反应力场，并利用该力场模拟了硝化甘油（NG）和 1,2,4-丁三醇三硝酸酯（BTTN）在不同温度（1500-3000 K）下的热分解过程，阐明了这两种高能物质的初始变化、中间产物和最终产物反应的详细机理。结果表明，NG 和 BTTN 的初始反应相似，主要反应涉及 O-NO2 键的裂解和 CC 键的解离。在 1500 K 时，O-NO2 键的断裂成为主要反应。中间产物 NO2、HNO2、NO 和 CH2O 的形成加速了化学反应。BTTN 最终产物中 CO2 和 H2O 的比例随温度的升高而发生显著变化。
{"title":"Pyrolysis reaction mechanisms of nitroglycerin (NG) and 1,2,4-butanetriol trinitrate (BTTN) using the ReaxFF force field","authors":"Yong Zhang , Zheng Mei , Ling-Chen Zhou , Jing Ye , Fang-Chao Hou , Bo-Cong Chen , Hao-Long Su , Jing Sun , Liang Song","doi":"10.1016/j.comptc.2024.114900","DOIUrl":"10.1016/j.comptc.2024.114900","url":null,"abstract":"<div><div>In this study, the ReaxFF-<em>lg</em> reactive force field was verified and employed to simulate the thermal decomposition of nitroglycerin (NG) and 1,2,4-butanetriol trinitrate (BTTN) at various temperatures (1500–3000 K), elucidating the detailed mechanisms of initial changes, intermediate products, and final product reactions for both energetic materials. The results indicate that the initial reactions of NG and BTTN are similar, and the primary reactions involve the cleavage of the O-NO<sub>2</sub> bond and the dissociation of the C<img>C bond. At 1500 K, the breakage of O-NO<sub>2</sub> bonds becomes the dominant reaction. As the temperature increases, in addition to the removal of NO<sub>2</sub>, the breakage of C<img>C chains is observed above 2000 K. The formation of intermediates NO<sub>2</sub>, HNO<sub>2</sub>, NO, and CH<sub>2</sub>O accelerates the chemical reaction. The proportions of CO<sub>2</sub> and H<sub>2</sub>O in the final products of BTTN change significantly with temperature.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114900"},"PeriodicalIF":3.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422838","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 : 2024-09-29DOI: 10.1016/j.comptc.2024.114897
Warood Kream Alaarage , Kasim Kadhim Alasedi , Abbas H. Abo Nasria , Tamadhur Alaa Hussein , Rajaa R. Abbas , Hayder H. Hussain
An examination was conducted on the electronic and optical characteristics of gas (H2S, CO2, CO, SO2, and SO) adsorption on a monolayer of InP using first-principles calculations based on DFT. To identify the optimal and most sensitive adsorption site for the adsorbed gases, four initial adsorption sites were selected. Various aspects such as adsorption distance, charge densities, and adsorption energy were analyzed across different types of adsorption to determine the most favorable adsorption configurations. Our research indicates that InP monolayers can chemically adsorb CO2, CO, SO2, and SO, forming new bonds with these gas molecules. Furthermore, H2S can be physically absorbed onto InP with a high level of adsorption energy. The optical findings reveal that the presence of gas molecules alters the conductivity and optical properties of the InP monolayer, especially noticeable in the UV range. InP emerges as a suitable material for detecting CO2, CO, SO2, and SO due to its distinct characteristics.
{"title":"A DFT investigation of monolayer InP: Effective toxic gas sensor with adsorption and optical response","authors":"Warood Kream Alaarage , Kasim Kadhim Alasedi , Abbas H. Abo Nasria , Tamadhur Alaa Hussein , Rajaa R. Abbas , Hayder H. Hussain","doi":"10.1016/j.comptc.2024.114897","DOIUrl":"10.1016/j.comptc.2024.114897","url":null,"abstract":"<div><div>An examination was conducted on the electronic and optical characteristics of gas (H<sub>2</sub>S, CO<sub>2</sub>, CO, SO<sub>2</sub>, and SO) adsorption on a monolayer of InP using first-principles calculations based on DFT. To identify the optimal and most sensitive adsorption site for the adsorbed gases, four initial adsorption sites were selected. Various aspects such as adsorption distance, charge densities, and adsorption energy were analyzed across different types of adsorption to determine the most favorable adsorption configurations. Our research indicates that InP monolayers can chemically adsorb CO<sub>2</sub>, CO, SO<sub>2</sub>, and SO, forming new bonds with these gas molecules. Furthermore, H<sub>2</sub>S can be physically absorbed onto InP with a high level of adsorption energy. The optical findings reveal that the presence of gas molecules alters the conductivity and optical properties of the InP monolayer, especially noticeable in the UV range. InP emerges as a suitable material for detecting CO<sub>2</sub>, CO, SO<sub>2</sub>, and SO due to its distinct characteristics.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114897"},"PeriodicalIF":3.0,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422929","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 : 2024-09-29DOI: 10.1016/j.comptc.2024.114899
Rahma El Mouhi , Ahmed Slimi , Souad El Khattabi , Adil Touimi Benjelloun , Asmae Fitri , Mohammed Benzakour , Mohammed Mcharfi , Mustafa Kurban
In this computational study, four donor–acceptor (D–A) small molecules were constructed using indacenodithiophene triphenylamine (IDTTPA) as the donor, with modifications made to the acceptor units intended for use in organic bulk heterojunction (BHJ) solar cells. Their electrical and optical properties were determined through density functional theory (DFT) and time-dependent DFT (TD-DFT) techniques. To ascertain the impact of acceptor group modifications on intramolecular electron delocalization and light absorption capabilities, several key variables were examined. Based on the results, it was determined that molecule SM4 demonstrated the best performance among the designed compounds. It exhibited a maximum wavelength of 594 nm, a narrow energy gap of 1.91 eV, a low-lying HOMO energy level of −4.512 eV in its absorption spectra, and a theoretical power conversion efficiency (PCE) of 8 %. This research provides valuable insights for the development of efficient D-A compounds for use in organic solar cells.
{"title":"Computational study of new small molecules D-A based on triphenylamines for bulk heterojunction solar cells (BHJ)","authors":"Rahma El Mouhi , Ahmed Slimi , Souad El Khattabi , Adil Touimi Benjelloun , Asmae Fitri , Mohammed Benzakour , Mohammed Mcharfi , Mustafa Kurban","doi":"10.1016/j.comptc.2024.114899","DOIUrl":"10.1016/j.comptc.2024.114899","url":null,"abstract":"<div><div>In this computational study, four donor–acceptor (D–A) small molecules were constructed using indacenodithiophene triphenylamine (IDTTPA) as the donor, with modifications made to the acceptor units intended for use in organic bulk heterojunction (BHJ) solar cells. Their electrical and optical properties were determined through density functional theory (DFT) and time-dependent DFT (TD-DFT) techniques. To ascertain the impact of acceptor group modifications on intramolecular electron delocalization and light absorption capabilities, several key variables were examined. Based on the results, it was determined that molecule SM4 demonstrated the best performance among the designed compounds. It exhibited a maximum wavelength of 594 nm, a narrow energy gap of 1.91 eV, a low-lying HOMO energy level of −4.512 eV in its absorption spectra, and a theoretical power conversion efficiency (PCE) of 8 %. This research provides valuable insights for the development of efficient D-A compounds for use in organic solar cells.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114899"},"PeriodicalIF":3.0,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422841","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 : 2024-09-28DOI: 10.1016/j.comptc.2024.114893
Zhi Zheng , Jun Shen , Zhenqing Han , Yu Chen , Yifan Bai
Ammonia-coal combustion mitigates CO2 emissions, yet nitrogen oxide emissions and char nitrogen oxidation mechanisms require further study. Our research employs density functional theory to explore coal char interactions with NO, NH3, and the impact of hydroxyls (–OH) and oxygen on reduction–oxidation processes. Findings indicate oxygen aids in forming hydroxyls on coal char, facilitating NO to NO2 conversion, lowering the activation energy for ammonia-coal oxidation to NO2. Oxygen also promotes char nitrogen oxidation to NO, reducing its activation energy. In NH3/coal/O2 systems, NH3 oxidation initiates NO formation. With the increase of the temperature, the reduction rate of NO by ammonia is always higher than the production rate of NO.
氨化煤燃烧可减少二氧化碳排放，但氮氧化物排放和煤炭氮氧化物机制还需要进一步研究。我们的研究采用密度泛函理论探索煤炭与 NO、NH3 的相互作用，以及羟基（-OH）和氧气对还原-氧化过程的影响。研究结果表明，氧气有助于在煤炭上形成羟基，促进 NO 向 NO2 的转化，降低氨-煤氧化成 NO2 的活化能。氧气还能促进煤炭氮氧化成 NO，降低其活化能。在 NH3/ 煤/O2 系统中，NH3 氧化会启动 NO 的形成。随着温度的升高，氨还原 NO 的速率总是高于 NO 的生成速率。
{"title":"Unveiling the role of oxygen in ammonia coal combustion: A DFT study on NOx emission mechanism","authors":"Zhi Zheng , Jun Shen , Zhenqing Han , Yu Chen , Yifan Bai","doi":"10.1016/j.comptc.2024.114893","DOIUrl":"10.1016/j.comptc.2024.114893","url":null,"abstract":"<div><div>Ammonia-coal combustion mitigates CO<sub>2</sub> emissions, yet nitrogen oxide emissions and char nitrogen oxidation mechanisms require further study. Our research employs density functional theory to explore coal char interactions with NO, NH<sub>3</sub>, and the impact of hydroxyls (–OH) and oxygen on reduction–oxidation processes. Findings indicate oxygen aids in forming hydroxyls on coal char, facilitating NO to NO<sub>2</sub> conversion, lowering the activation energy for ammonia-coal oxidation to NO<sub>2</sub>. Oxygen also promotes char nitrogen oxidation to NO, reducing its activation energy. In NH<sub>3</sub>/coal/O<sub>2</sub> systems, NH<sub>3</sub> oxidation initiates NO formation. With the increase of the temperature, the reduction rate of NO by ammonia is always higher than the production rate of NO.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114893"},"PeriodicalIF":3.0,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359586","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 : 2024-09-28DOI: 10.1016/j.comptc.2024.114895
Tianyan Jiang , Feifan Wu , Hao Wu , Haonan Xie , Biao Deng , Maoqiang Bi
This paper investigates the potential of palladium (Pd) and its clusters-doped tungsten ditelluride (WTe2) monolayer materials for the detection of dissolved gases (such as CH4, C2H2, and C2H4) in transformer oil. Density functional theory (DFT) was used to study the effect of Pdn (n = 1–4) doping on the gas sensing and adsorption properties of WTe2 monolayer materials. The results show that Pdn doping can significantly improve the adsorption capacity and gas sensing performance of WTe2 to these gas molecules, especially showing excellent performance in detecting acetylene and ethylene. Studies have shown that Pdn doping improves the electrical conductivity of WTe2, making it more suitable for the development of gas sensors. Through the calculation of state density, molecular orbital and charge density difference, the adsorption mechanism of Pdn-doped WTe2 monolayer to different gas molecules was revealed. This study provides a theoretical basis and guidance for the development of efficient sensor materials for fault gas detection in transformer oil. In conclusion, the proposed Pd-doped WTe2 monolayer demonstrates promising potential for detecting dissolved gases in transformer oil. Future work will focus on experimental validation and further optimization of the material’s sensitivity and selectivity towards other gas species.
{"title":"Adsorption and gas sensing properties of CH4, C2H2, and C2H4 dissolved gases in transformer oil on Pdn(n = 1–4)-doped WTe2 monolayers: A DFT study","authors":"Tianyan Jiang , Feifan Wu , Hao Wu , Haonan Xie , Biao Deng , Maoqiang Bi","doi":"10.1016/j.comptc.2024.114895","DOIUrl":"10.1016/j.comptc.2024.114895","url":null,"abstract":"<div><div>This paper investigates the potential of palladium (Pd) and its clusters-doped tungsten ditelluride (WTe<sub>2</sub>) monolayer materials for the detection of dissolved gases (such as CH<sub>4</sub>, C<sub>2</sub>H<sub>2</sub>, and C<sub>2</sub>H<sub>4</sub>) in transformer oil. Density functional theory (DFT) was used to study the effect of Pd<sub>n</sub> (n = 1–4) doping on the gas sensing and adsorption properties of WTe<sub>2</sub> monolayer materials. The results show that Pd<sub>n</sub> doping can significantly improve the adsorption capacity and gas sensing performance of WTe<sub>2</sub> to these gas molecules, especially showing excellent performance in detecting acetylene and ethylene. Studies have shown that Pd<sub>n</sub> doping improves the electrical conductivity of WTe<sub>2</sub>, making it more suitable for the development of gas sensors. Through the calculation of state density, molecular orbital and charge density difference, the adsorption mechanism of Pd<sub>n</sub>-doped WTe<sub>2</sub> monolayer to different gas molecules was revealed. This study provides a theoretical basis and guidance for the development of efficient sensor materials for fault gas detection in transformer oil. In conclusion, the proposed Pd-doped WTe<sub>2</sub> monolayer demonstrates promising potential for detecting dissolved gases in transformer oil. Future work will focus on experimental validation and further optimization of the material’s sensitivity and selectivity towards other gas species.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114895"},"PeriodicalIF":3.0,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142442407","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 numerical research explores the structural stability, phonons, electronic, and optical properties of tetragonal HfxSi1-xO2 solid solutions for the rates x = 0.25, 0.5, and 0.75, respectively. During this numerical investigation, the Full-Potential Linearized Augmented Plane Wave method (FP-LAPW) based on the Density Functional Theory (DFT) was employed. Total energy calculations and structure relaxations were carried out using the Perdew-Burke-Ernzerhof Generalized Gradient Approximation (PBE-GGA). For electronic properties, we adopted the Tran-Blaha-modified Becke-Johnson (TB-mBJ) function. According to phonon properties, cohesiveness, and formation energy, these alloys have strong thermodynamic stability and could be produced and synthesized experimentally in a laboratory. The structural parameters are in good agreement with the available results for all compounds. From the electronic properties, HfSi3O8 has a small direct band gap in the ΓV- ΓC direction via GGA approximation, equal to 1.541 eV, indicating that the HfSi3O8 material is one of the future-efficient materials for the solar cell fabrication process. However, HfSiO4 and Hf3SiO8 exhibit a large indirect band gap in the ΓV-MC direction, equal to 5.328 eV and 4.284 eV, using GGA approximation, respectively. Motivated by the prospect of using its interesting electronic structure for optoelectronic semiconductor applications, the optical properties of HfSi3O8, HfSiO4, and Hf3SiO8 were studied. This numerical research highlights this material as the first of its kind in terms of optical properties. Given the scarcity of theoretical and experimental data, the current study may be useful for future research on these compounds. Our findings can thus pave the way for further research into the potential use of these oxide compounds in a variety of chemical, physical, and electrical applications aimed at meeting socioeconomic requirements.
{"title":"A comprehensive numerical investigation on structural stability, mechanical, and optoelectronic properties of HfxSi1‑xO2 tetragonal compounds from the hafnon Family","authors":"Amira Nour Asfora , Slimane Haid , Mawloud Ould Moussa","doi":"10.1016/j.comptc.2024.114894","DOIUrl":"10.1016/j.comptc.2024.114894","url":null,"abstract":"<div><div>This numerical research explores the structural stability, phonons, electronic, and optical properties of tetragonal Hf<sub>x</sub>Si<sub>1-x</sub>O<sub>2</sub> solid solutions for the rates <em>x</em> = 0.25, 0.5, and 0.75, respectively. During this numerical investigation, the Full-Potential Linearized Augmented Plane Wave method (FP-LAPW) based on the Density Functional Theory (DFT) was employed. Total energy calculations and structure relaxations were carried out using the Perdew-Burke-Ernzerhof Generalized Gradient Approximation (PBE-GGA). For electronic properties, we adopted the Tran-Blaha-modified Becke-Johnson (TB-mBJ) function. According to phonon properties, cohesiveness, and formation energy, these alloys have strong thermodynamic stability and could be produced and synthesized experimentally in a laboratory. The structural parameters are in good agreement with the available results for all compounds. From the electronic properties, HfSi<sub>3</sub>O<sub>8</sub> has a small direct band gap in the Γ<sub>V</sub>-<!--> <!-->Γ<sub>C</sub> direction via GGA approximation, equal to 1.541 eV, indicating that the HfSi<sub>3</sub>O<sub>8</sub> material is one of the future-efficient materials for the solar cell fabrication process. However, HfSiO<sub>4</sub> and Hf<sub>3</sub>SiO<sub>8</sub> exhibit a large indirect band gap in the Γ<sub>V</sub>-M<sub>C</sub> direction, equal to 5.328 eV and 4.284 eV, using GGA approximation, respectively. Motivated by the prospect of using its interesting electronic structure for optoelectronic semiconductor applications, the optical properties of HfSi<sub>3</sub>O<sub>8</sub>, HfSiO<sub>4</sub>, and Hf<sub>3</sub>SiO<sub>8</sub> were studied. This numerical research highlights this material as the first of its kind in terms of optical properties. Given the scarcity of theoretical and experimental data, the current study may be useful for future research on these compounds. Our findings can thus pave the way for further research into the potential use of these oxide compounds in a variety of chemical, physical, and electrical applications aimed at meeting socioeconomic requirements.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114894"},"PeriodicalIF":3.0,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422928","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 : 2024-09-27DOI: 10.1016/j.comptc.2024.114892
Junkai Wang , Yixuan Cai , Shumin Yu , Qianku Hu , Aiguo Zhou , Shaowei Zhang
Developing efficient catalysts for the conversion of methane (CH4) to methanol (CH3OH) remains a critical challenge in the chemical industry, with significant implications for both energy production and environmental sustainability. This study pioneers the exploration of the Sc/Ti-Ti2CO2 single-atom catalysts (SACs) for this transformation, utilizing density functional theory (DFT) calculations. Notably, our findings reveal that Sc and Ti are uniquely stable on the Ti2CO2 MXene surface, a discovery that could inform future catalyst designs. We also demonstrate that while CH4 weakly physisorbs on the Sc/Ti-Ti2CO2 surface, N2O molecules decompose directly into N2 and highly reactive O* species, which bind with Sc/Ti to drive the catalytic process. The oxidation of CH4 proceeds in two steps: CH4 + O* → CH3* + OH* with reaction barriers of 0.58 eV (Sc) and 1.38 eV (Ti), followed by CH3* + OH* → CH3OH with barriers of 1.5 eV (Sc) and 1.61 eV (Ti). Importantly, the low desorption energy of CH3OH, especially on Sc (0.85 eV), highlights the exceptional catalytic potential of Sc/Ti2CO2 for the direct conversion of CH4 to CH3OH. These results not only underscore the feasibility of using MXene-based SACs for CH4 oxidation but also provide a theoretical foundation for the development of highly efficient catalysts in this domain.
{"title":"First-principles investigation of methane to methanol conversion on Ti2CO2 MXene supported single-atom catalyst","authors":"Junkai Wang , Yixuan Cai , Shumin Yu , Qianku Hu , Aiguo Zhou , Shaowei Zhang","doi":"10.1016/j.comptc.2024.114892","DOIUrl":"10.1016/j.comptc.2024.114892","url":null,"abstract":"<div><div>Developing efficient catalysts for the conversion of methane (CH<sub>4</sub>) to methanol (CH<sub>3</sub>OH) remains a critical challenge in the chemical industry, with significant implications for both energy production and environmental sustainability. This study pioneers the exploration of the Sc/Ti-Ti<sub>2</sub>CO<sub>2</sub> single-atom catalysts (SACs) for this transformation, utilizing density functional theory (DFT) calculations. Notably, our findings reveal that Sc and Ti are uniquely stable on the Ti<sub>2</sub>CO<sub>2</sub> MXene surface, a discovery that could inform future catalyst designs. We also demonstrate that while CH<sub>4</sub> weakly physisorbs on the Sc/Ti-Ti<sub>2</sub>CO<sub>2</sub> surface, N<sub>2</sub>O molecules decompose directly into N<sub>2</sub> and highly reactive O* species, which bind with Sc/Ti to drive the catalytic process. The oxidation of CH<sub>4</sub> proceeds in two steps: CH<sub>4</sub> + O* → CH<sub>3</sub>* + OH* with reaction barriers of 0.58 eV (Sc) and 1.38 eV (Ti), followed by CH<sub>3</sub>* + OH* → CH<sub>3</sub>OH with barriers of 1.5 eV (Sc) and 1.61 eV (Ti). Importantly, the low desorption energy of CH<sub>3</sub>OH, especially on Sc (0.85 eV), highlights the exceptional catalytic potential of Sc/Ti<sub>2</sub>CO<sub>2</sub> for the direct conversion of CH<sub>4</sub> to CH<sub>3</sub>OH. These results not only underscore the feasibility of using MXene-based SACs for CH<sub>4</sub> oxidation but also provide a theoretical foundation for the development of highly efficient catalysts in this domain.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114892"},"PeriodicalIF":3.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422803","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 : 2024-09-27DOI: 10.1016/j.comptc.2024.114885
Dmitri G. Fedorov
The disulfide bond order is analyzed in terms of localized molecular orbitals. Several schemes of fragment boundaries are proposed for defining fragments in proteins with sulfur bridges, and their accuracy is evaluated for the three-body expansion of the fragment molecular orbital method. Interactions of the ligand ibuprofen with residues in prostaglandin H(2) synthase-1 (PDB: 1EQG) are analyzed at the MP2 level. The role of sulfur bridges in the protein stability and ligand binding is discussed.
{"title":"Fragmentation of disulfide bonds in the fragment molecular orbital method","authors":"Dmitri G. Fedorov","doi":"10.1016/j.comptc.2024.114885","DOIUrl":"10.1016/j.comptc.2024.114885","url":null,"abstract":"<div><div>The disulfide bond order is analyzed in terms of localized molecular orbitals. Several schemes of fragment boundaries are proposed for defining fragments in proteins with sulfur bridges, and their accuracy is evaluated for the three-body expansion of the fragment molecular orbital method. Interactions of the ligand ibuprofen with residues in prostaglandin H(2) synthase-1 (PDB: 1EQG) are analyzed at the MP2 level. The role of sulfur bridges in the protein stability and ligand binding is discussed.</div></div>","PeriodicalId":284,"journal":{"name":"Computational and Theoretical Chemistry","volume":"1241 ","pages":"Article 114885"},"PeriodicalIF":3.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422804","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号