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Metal center modulation of micro-structures, luminescence, and metronidazole sensing abilities for metal-organic frameworks 金属有机骨架的微结构、发光和甲硝唑感应能力的金属中心调制
IF 2.4 3区 化学
Polyhedron Pub Date : 2025-07-24 DOI: 10.1016/j.poly.2025.117706
Shuaixing Wang , Shunchang Zhao , Jiamin Wang , Dejing Yin , Chi Zhang , Jinfang Zhang
{"title":"Metal center modulation of micro-structures, luminescence, and metronidazole sensing abilities for metal-organic frameworks","authors":"Shuaixing Wang ,&nbsp;Shunchang Zhao ,&nbsp;Jiamin Wang ,&nbsp;Dejing Yin ,&nbsp;Chi Zhang ,&nbsp;Jinfang Zhang","doi":"10.1016/j.poly.2025.117706","DOIUrl":"10.1016/j.poly.2025.117706","url":null,"abstract":"<div><div>This study explores the role of metal centers in regulating the micro-structure, luminescence, and sensing ability of MOFs. Two three-dimensional (3-D) luminescent metal-organic frameworks (LMOFs) [M₂(<strong>L</strong>)(OBBA)₂]ₙ [M<sup>2+</sup> = Co<sup>2+</sup> (<strong>1</strong>), Zn<sup>2+</sup> (<strong>2</strong>)] were constructed by different metal centers (Co<sup>2+</sup>/Zn<sup>2+</sup>) and same organic bridging ligands 4,4′-(((9H-fluoren-9-ylidene)methylene)bis(4,1-phenylene))dipyridine (<strong>L</strong>) and 4,4′-oxybisbenzoic acid (H<sub>2</sub>OBBA). Their frameworks feature different skeletal binuclear clusters [M<sub>2</sub>(COO)<sub>4</sub>] (M = Co, Zn) and exhibit same double-interpenetrated <em>pcu</em> topology. The distinct electronic configurations of Co<sup>2+</sup> (d<sup>7</sup>) and Zn<sup>2+</sup> (d<sup>10</sup>) govern their luminescent properties. Compared with <strong>L</strong>, <strong>1</strong> and <strong>2</strong> display blue-shifted excitation (335 nm) and red-shifted excitation (355 nm), respectively. They demonstrate luminescent sensing metronidazole (MDZ) performance. Especially, <strong>1</strong> has superior sensing sensitivity with a Stern-Volmer constant (<em>K</em><sub><em>SV</em></sub> = 1.71 × 10<sup>4</sup> M<sup>−1</sup>) and a low detection limit (1.03 × 10<sup>−3</sup> mM). MDZ sensing mechanism of them has been explored in detail. This work reveals the critical role of metal electronic configurations in designing efficient fluorescent sensors.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117706"},"PeriodicalIF":2.4,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144713477","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}
引用次数: 0
Corrigendum to “Structural characterizations, BFDH morphology, DSC, infrared and Raman vibrational studies of the tetramethylammonium nonachlorodibismuthate [(CH3)4N]3Bi2Cl9” [Polyhedron 251 (2024) 116875] “非氯二铋酸四甲基铵[(CH3)4N]3Bi2Cl9的结构表征、BFDH形态、DSC、红外和拉曼振动研究”的勘误[Polyhedron 251 (2024) 116875]
IF 2.6 3区 化学
Polyhedron Pub Date : 2025-07-24 DOI: 10.1016/j.poly.2025.117702
A. Ouasri , F. Lambarki , R. Fakhreddine , A. Aatiq , A. Rhandour
{"title":"Corrigendum to “Structural characterizations, BFDH morphology, DSC, infrared and Raman vibrational studies of the tetramethylammonium nonachlorodibismuthate [(CH3)4N]3Bi2Cl9” [Polyhedron 251 (2024) 116875]","authors":"A. Ouasri ,&nbsp;F. Lambarki ,&nbsp;R. Fakhreddine ,&nbsp;A. Aatiq ,&nbsp;A. Rhandour","doi":"10.1016/j.poly.2025.117702","DOIUrl":"10.1016/j.poly.2025.117702","url":null,"abstract":"","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117702"},"PeriodicalIF":2.6,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144842944","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}
引用次数: 0
Synthesis and characterization of highly selective nickel(II) catalysts for styrene oxidation using m-CPBA as oxidant 以m-CPBA为氧化剂氧化苯乙烯的高选择性镍(II)催化剂的合成与表征
IF 2.6 3区 化学
Polyhedron Pub Date : 2025-07-24 DOI: 10.1016/j.poly.2025.117705
Na Xing, Yifan Xing, Shu Li, Yuanyuan Zhang, Yu Zhang, Wenqing Jian, Shiyu Zhang
{"title":"Synthesis and characterization of highly selective nickel(II) catalysts for styrene oxidation using m-CPBA as oxidant","authors":"Na Xing,&nbsp;Yifan Xing,&nbsp;Shu Li,&nbsp;Yuanyuan Zhang,&nbsp;Yu Zhang,&nbsp;Wenqing Jian,&nbsp;Shiyu Zhang","doi":"10.1016/j.poly.2025.117705","DOIUrl":"10.1016/j.poly.2025.117705","url":null,"abstract":"<div><div>Three novel nickel(II) complexes, [Ni<sub>2</sub>(L<sup>a</sup>)<sub>2</sub>(μ<sub>1,1,3</sub>-N<sub>3</sub>)<sub>2</sub>]<sub>n</sub> (<strong>1</strong>), [Ni<sub>3</sub>(L<sup>a</sup>)<sub>2</sub>(CH<sub>3</sub>COO)<sub>2</sub>(μ<sub>1,1</sub>-N<sub>3</sub>)<sub>2</sub>(DMF)<sub>2</sub>] (<strong>2</strong>), and [Ni<sub>3</sub>(L<sup>b</sup>)<sub>2</sub>(μ<sub>2</sub>-η<sup>1</sup>:η<sup>1</sup>-OAc)<sub>2</sub>(μ<sub>2</sub>-η<sup>2</sup>:η<sup>1</sup>-OAc)<sub>2</sub>]0.5H<sub>2</sub>O (<strong>3</strong>), were synthesized using Schiff base ligands (L<sup>a</sup> and L<sup>b</sup> are the deprotonated form of 5-bromo-2-((2-ethylaminoethylimino)methyl)phenol (HL<sup>a</sup>) and 5-bromo-2-((2-diethylaminoethylimino)methyl)phenol (HL<sup>b</sup>)), and characterized by elemental analysis, IR, UV–Vis, single-crystal X-ray diffraction, and thermogravimetry. These complexes were evaluated as catalysts for styrene oxidation under mild conditions (50 °C) using m-CPBA as the oxidant. Remarkably, complex <strong>1</strong> demonstrated exceptional selectivity (98.4 %) toward styrene oxide (SO), surpassing previously reported nickel-based catalysts at lower temperatures. Mechanistic studies revealed that m-CPBA significantly inhibits the further oxidation of SO to benzaldehyde (BA), thereby enhancing SO selectivity. Additionally, CCl<sub>4</sub> was identified as the optimal solvent, contrasting with the commonly used CH<sub>3</sub>CN in literature. This work provides a high-efficiency, low-temperature catalytic system for styrene oxidation, offering insights into the role of oxidants and solvent effects in tuning product selectivity.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117705"},"PeriodicalIF":2.6,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144767084","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}
引用次数: 0
To highlight the roles of NH⋯O, CH⋯O, and CH⋯π interactions in stabilizing 1D supramolecular assemblies of two discrete dinuclear zinc compounds by MEP and QTAIM/NCIPlot analysis 通过MEP和QTAIM/NCIPlot分析,突出NH⋯O, CH⋯O和CH⋯π相互作用在稳定两种离散双核锌化合物的一维超分子组装中的作用
IF 2.6 3区 化学
Polyhedron Pub Date : 2025-07-22 DOI: 10.1016/j.poly.2025.117701
Biplab Halder , Puspendu Middya , Antonio Frontera , Shouvik Chattopadhyay
{"title":"To highlight the roles of NH⋯O, CH⋯O, and CH⋯π interactions in stabilizing 1D supramolecular assemblies of two discrete dinuclear zinc compounds by MEP and QTAIM/NCIPlot analysis","authors":"Biplab Halder ,&nbsp;Puspendu Middya ,&nbsp;Antonio Frontera ,&nbsp;Shouvik Chattopadhyay","doi":"10.1016/j.poly.2025.117701","DOIUrl":"10.1016/j.poly.2025.117701","url":null,"abstract":"<div><div>In this manuscript we report the synthesis and characterization of two dinuclear zinc compounds, [(μ-OAc)<sub>2</sub>Zn<sub>2</sub>L<sup>1</sup>(OAc)] (<strong>1</strong>) and [(μ-OAc)<sub>2</sub>Zn<sub>2</sub>L<sup>2</sup>(OAc)]⋅H<sub>2</sub>O (<strong>2</strong>), using two tetradentate ligands respectively, HL<sup>1</sup> {2-(((2-(diethylamino)ethyl)amino)methyl)-6-methoxyphenol} and HL<sup>2</sup> {2-(((2-(dimethylamino)ethyl)amino)methyl)-6-ethoxyphenol}. The structures were confirmed by single-crystal X-ray diffraction analysis. Both compounds <strong>1</strong> and <strong>2</strong> forms 1-D supramolecular chains in the solid state by N<img>H⋯O and C<img>H⋯O hydrogen bonding interaction respectively. The DFT analysis began with the computation of MEP surfaces to identify the regions of maximum positive and negative potential within the molecules.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117701"},"PeriodicalIF":2.6,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144749858","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}
引用次数: 0
High-efficient colorimetric detection of sulfide and silver ions based on a long-wavelength absorbing carbocyanine dye 基于长波长吸收碳菁染料的硫化物和银离子的高效比色检测
IF 2.6 3区 化学
Polyhedron Pub Date : 2025-07-21 DOI: 10.1016/j.poly.2025.117699
Haoyun Lu, Kun Zhang, Liping Gao
{"title":"High-efficient colorimetric detection of sulfide and silver ions based on a long-wavelength absorbing carbocyanine dye","authors":"Haoyun Lu,&nbsp;Kun Zhang,&nbsp;Liping Gao","doi":"10.1016/j.poly.2025.117699","DOIUrl":"10.1016/j.poly.2025.117699","url":null,"abstract":"<div><div>The high-efficient detection of specific inorganic ions in H<sub>2</sub>O is extremely important, and monitoring S<sup>2−</sup> and Ag<sup>+</sup> is of great significance because their abnormal levels will lead to many environmental and health problems. Herein we propose a long-wavelength absorbing carbocyanine dye DIDS-Li as a colorimetric probe to detect S<sup>2−</sup> and Ag<sup>+</sup> based on color changes induced by structural changes of DIDS-Li. Sensing results suggest that the S<sup>2−</sup> will cause the azure DIDS-Li to become colorless and the Ag<sup>+</sup> causes DIDS-Li to become bright yellow. This colorimetric probe also shows the good immunity to interference, a wide linear response range, and quantitative accuracy of S<sup>2−</sup> and Ag<sup>+</sup> detections in natural water samples. Meanwhile, we also develop a smartphone analysis method that greatly improves the real-time detection ability of DIDS-Li for S<sup>2−</sup> and Ag<sup>+</sup>. This work elucidates the relationship between carbocyanine dye and inorganic ions which offers a new means for efficient detection of S<sup>2−</sup> and Ag<sup>+</sup> and the new idea for the application of carbocyanine dyes in colorimetric detection.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117699"},"PeriodicalIF":2.6,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144749857","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}
引用次数: 0
Coordination polymer of Co (II) with 5-sulfosalysilic acid: synthesis, structure, Hirshfeld surface analysis, theoretical calculations and adsorption properties Co (II) - 5-磺基硅酸配位聚合物:合成、结构、Hirshfeld表面分析、理论计算和吸附性能
IF 2.4 3区 化学
Polyhedron Pub Date : 2025-07-20 DOI: 10.1016/j.poly.2025.117674
Normamatov Adkhamjon Sadullayevich , Hoji Akber Aisa , Zhao Jiangyu , Nguyen Thi Thu Ha , Nguyen Ngoc Ha , Ruzmetov Abror Khamidjanovich , Yakubov Yuldosh Yusupboevich , Adizov Bobirjon Zamirovich , Mamatkodirov D. Behzodjon , Ibragimov Bakhtiyar Tulyaganovich , Ikram I. Abdullaev , Junkuo Gao , Ibragimov Aziz Bakhtiyarovich
{"title":"Coordination polymer of Co (II) with 5-sulfosalysilic acid: synthesis, structure, Hirshfeld surface analysis, theoretical calculations and adsorption properties","authors":"Normamatov Adkhamjon Sadullayevich ,&nbsp;Hoji Akber Aisa ,&nbsp;Zhao Jiangyu ,&nbsp;Nguyen Thi Thu Ha ,&nbsp;Nguyen Ngoc Ha ,&nbsp;Ruzmetov Abror Khamidjanovich ,&nbsp;Yakubov Yuldosh Yusupboevich ,&nbsp;Adizov Bobirjon Zamirovich ,&nbsp;Mamatkodirov D. Behzodjon ,&nbsp;Ibragimov Bakhtiyar Tulyaganovich ,&nbsp;Ikram I. Abdullaev ,&nbsp;Junkuo Gao ,&nbsp;Ibragimov Aziz Bakhtiyarovich","doi":"10.1016/j.poly.2025.117674","DOIUrl":"10.1016/j.poly.2025.117674","url":null,"abstract":"<div><div>A new tetraaqua coordination polymer (CP) of Co based on 5-sulfosalicylic acid (5-SSA) has been synthesized, and its structure determined via single-crystal X-ray crystallography. Characterization included elemental analysis, UV and IR spectroscopy, and theoretical calculations. Each Co(II) ion is coordinated by two oxygen atoms from 5-SSA ligands and four water molecules. The polymeric unit consists of a 1-D fragment formed by metal ion associations, with bond lengths to oxygen ranging from 2.062 to 2.137 Å and bond angles between 83.72° and 96.32°, resulting in a slightly distorted octahedral geometry. An isostructural Zn-complex of 5-SSA is found in the Cambridge Structural Database.</div><div>Theoretical calculations closely match the X-ray results. Sorption properties measured with an automated gas sorption device reveal a Brunauer-Emmett-Teller surface area of 105.33 m<sup>2</sup>/g, an average pore diameter of 56.34 Å, and an adsorption capacity of 0.16 cm<sup>3</sup>/g. Theoretical adsorption energies for N₂ and NO are −18.5 kJ mol<sup>−1</sup> and −73.2 kJ mol<sup>−1</sup>, indicating favorable adsorption, with the stronger chemisorption of polar NO suggesting potential as a sensor material. Hirshfeld surface analysis shows major intermolecular interactions as H<img>O/O<img>H (55.1 %) and H<img>H contacts (24 %).</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117674"},"PeriodicalIF":2.4,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686131","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}
引用次数: 0
Strong antiferromagnetic exchange in three methoxido-bridged dinuclear copper(II) complexes showing the effect of an oxine-meta-xylylene framework and different auxiliary ligands – Structural, magnetic and theoretical studies with catecholase activity 三种甲氧基桥接双核铜(II)配合物在氧-间二甲苯框架和不同辅助配体作用下的强反铁磁交换——儿茶酚酶活性的结构、磁性和理论研究
IF 2.4 3区 化学
Polyhedron Pub Date : 2025-07-19 DOI: 10.1016/j.poly.2025.117697
Muna R.A. Al-Mandhary , Sindhu Menon , Jim Simpson , John McAdam , Mai Ozaki , Makoto Handa , Masahiro Mikuriya
{"title":"Strong antiferromagnetic exchange in three methoxido-bridged dinuclear copper(II) complexes showing the effect of an oxine-meta-xylylene framework and different auxiliary ligands – Structural, magnetic and theoretical studies with catecholase activity","authors":"Muna R.A. Al-Mandhary ,&nbsp;Sindhu Menon ,&nbsp;Jim Simpson ,&nbsp;John McAdam ,&nbsp;Mai Ozaki ,&nbsp;Makoto Handa ,&nbsp;Masahiro Mikuriya","doi":"10.1016/j.poly.2025.117697","DOIUrl":"10.1016/j.poly.2025.117697","url":null,"abstract":"<div><div>The synthetic versatility of ligands formed by coupling oxine units with <em>m</em>-xylylene has resulted in the self-assembly of three methoxido–bridged dinuclear copper(II) complexes with the formula, [CuOCH<sub>3</sub>X]<sub>2</sub>L1, X = Br<sup>−</sup> (<strong>1</strong>), Cl<sup>−</sup> (<strong>2</strong>), NO<sub>3</sub><sup>−</sup> (<strong>3</strong>) and L1 = 1,3-bis(8-quinolyl-oxymethyl)benzene. The complexes are isostructural, showing distorted square pyramidal geometry for each copper(II) ion. The Cu-O-Cu bridging angle of approximately 104° in all three cases favours strong antiferromagnetic exchange coupling. The effect of the auxiliary ligand is observed in the gradation of magnetic and catalytic properties. Variable temperature magnetic susceptibility gives exchange coupling constants, <em>J</em> values, between −500 and −310 cm<sup>−1</sup>, indicative of strong antiferromagnetic coupling involving the methoxido-bridged units with subtler effects due to the auxiliary ligands. EPR behaviour is consistent with a diamagnetic ground state arising from substantial antiferromagnetic coupling. DFT calculations provided theoretical validation with <em>J</em> values estimated between −565 and −400 cm<sup>−1</sup> for the three complexes, and revealed spin delocalization over the coordination spheres including the auxiliary ligands. Catalysis of catechol by the three complexes followed Michaelis-Menten kinetics and displayed relatively high turnover numbers (between 2.3 and 6.0 × 10<sup>2</sup> h<sup>−1</sup>) in comparison with other alkoxido bridged dinuclear copper(II) complexes, thus making these complexes good functional mimics of the native enzyme with respect to magnetic and catalytic properties.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117697"},"PeriodicalIF":2.4,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144696774","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}
引用次数: 0
Rare-gas excimers and exciplexes: Surprising challenges for time-dependent Density Functional Theory approaches 稀有气体准分子和杂合体:时变密度泛函理论方法的惊人挑战
IF 2.6 3区 化学
Polyhedron Pub Date : 2025-07-18 DOI: 10.1016/j.poly.2025.117678
Ariel C. Jones , Tobias F. Loeff , Benjamin J. Heath , Lars Goerigk
{"title":"Rare-gas excimers and exciplexes: Surprising challenges for time-dependent Density Functional Theory approaches","authors":"Ariel C. Jones ,&nbsp;Tobias F. Loeff ,&nbsp;Benjamin J. Heath ,&nbsp;Lars Goerigk","doi":"10.1016/j.poly.2025.117678","DOIUrl":"10.1016/j.poly.2025.117678","url":null,"abstract":"<div><div>Excimers (excited dimers of identical monomers) and exciplexes (excited complexes of distinct monomers) are bound by interactions including electrostatics, charge transfer, London dispersion, and excitonic splitting (excimers only). As such, these systems are challenging to describe theoretically. Time-dependent Density Functional Theory (TD-DFT) is the mostly widely used approach for excited-state computational chemistry; however, it is not yet clear whether such methods are able to adequately describe excimer and exciplex binding. In this work, we present a systematic TD-DFT benchmarking study of rare-gas excimers and exciplexes. Interaction energy curves are computed for these systems with CC3/aug-cc-pV5Z as an accurate reference. 79 variations of dispersion-corrected and uncorrected TD-DFT methods are benchmarked that span Jacob’s ladder and include recent spin-scaled double-hybrids. It is shown that TD-DFT tends to overbind the rare-gas excimers and exciplexes. This is surprising given that TD-DFT has known limitations in describing London dispersion forces which typically results in underbound complexes. The overbinding of rare-gas excimers is attributed to red-shifted excitation energies of their Rydberg states. The Helium excimer has particularly strong binding arising from large excitonic splitting. For this excimer, TD-DFT is generally underbinding, which is due to greater long-range character for the dissociated monomers compared to the bound excimer. On average, double-hybrid TD-DFT methods are the most robust and in particular SCS-PBE-QIDH has the lowest mean absolute error (1.18 kcal mol<sup>−1</sup>). There remains a need for additional benchmarking and method development to address the various interactions involved in excimer and exciplex binding.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117678"},"PeriodicalIF":2.6,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144767137","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}
引用次数: 0
Understanding the role of oxygen vacancies in SrTiO3/LaAlO3 interfaces from first principles study 从第一性原理研究了解SrTiO3/LaAlO3界面中氧空位的作用
IF 2.6 3区 化学
Polyhedron Pub Date : 2025-07-18 DOI: 10.1016/j.poly.2025.117695
Ali H. Reshak
{"title":"Understanding the role of oxygen vacancies in SrTiO3/LaAlO3 interfaces from first principles study","authors":"Ali H. Reshak","doi":"10.1016/j.poly.2025.117695","DOIUrl":"10.1016/j.poly.2025.117695","url":null,"abstract":"<div><div>We have investigated the influence of oxygen vacancies on the electronic structure of 6.5STO/1.5LAO n-type interfaces. An 6.5STO/1.5LAO n-type interface along the (001) direction has been built. Then one oxygen atom has been removed to investigate the influence of an oxygen vacancy on the resulting properties. The original structure is designated as I and the one with O-vacancy as II. On the basis of that, a theoretical model originating from the designed O-vacancies was proposed to investigate the influence of the O-vacancy on the band structure and the associated properties. It was found that the O-vacancy leads to an increase in the effective masses and the density of states at the Fermi level (E<sub>F</sub>). Moreover, the O-vacancy leads to an increase in the valence electrons (V<em>e</em><sup>−</sup>). By increasing the V<em>e</em><sup>−</sup> number, additional electrons (<em>e</em><sup>−</sup>) are added to the <em>d</em>-band at E<sub>F</sub>. This leads to an increase of the carrier concentration. The calculated electronic charge density distribution is used to explore the influence of the O-vacancy on the bonding nature, charge transfer and electronic charge distribution. The O-vacancy adds two extra <em>e</em><sup>−</sup> to the interface to preserve charge neutrality. Adding 1e/unit cell or 0.5e/unit cell to the interface is enough to maintain overall neutrality. Moreover, the conductivity can be achieved only when The LaAlO<sub>3</sub>/SrTiO<sub>3</sub> interface is along the 001 crystallographic direction. The electrons at the interface between LAO/STO are free to move parallel to the interface (xy plane), but are confined in the z direction (001) and thus can be thought of a two dimensional sheet of electrons sandwiched between two insulators. Interesting phenomena can result from this confinement of electrons in two dimensions due to the quantization of the electrons energy levels in the z-direction.</div></div>","PeriodicalId":20278,"journal":{"name":"Polyhedron","volume":"280 ","pages":"Article 117695"},"PeriodicalIF":2.6,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724360","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}
引用次数: 0
Two steps post-synthesis of MOF-303 for design a bi-metal catalyst: response surface methodology (RSM) optimization, kinetics and thermodynamic study MOF-303合成后双金属催化剂设计的两步:响应面法优化、动力学和热力学研究
IF 2.4 3区 化学
Polyhedron Pub Date : 2025-07-17 DOI: 10.1016/j.poly.2025.117698
Farzaneh Rouhani, Radmehr Rahimi-Moslehabadi, Matin Shirzad
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