Theoretical calculations using a density functional theory (DFT) approach has been utilized to explore the structural, electronic, and optical properties of Ti3C2, Ti3C2Tx, Tx = NO, and its alloys ...with Group IIIA elements (Al, Ga, In, Tl) as electrode materials for supercapacitor devices. The results show good crystal stability and an increase in the metallic property of the functionalized/alloyed MXenes (Ti3C2NO, AlTi3C2NO, GaTi3C2NO, InTi3C2NO, and Tl Ti3C2NO) making them better candidates for application as electrode materials. The band structures of the studied compounds revealed a direct band interaction and a progressive increase in the overlap of the bands upon introducing the terminating group (NO) and when alloyed with Al, Ga, In, and Tl. The partial and total density of states of the studied compounds confirmed their metallic behaviour and conductivity. The spin-polarized band structures and spin-polarized DOS of the compounds studied have revealed their antiferromagnetic properties, while TlTi3C2NO showed an interesting non-collinear spin-polarized structure, which is indicative of a great Nerst effect. Our density of states calculations demonstrates a good interaction was formed in the valence orbitals of the studied compounds with a Fermi level of 0 eV, which is indicative of a good conductor and a metallic character. The quantum capacitance of the studied compounds (MXenes) revealed an improved QC upon surface functionalization and alloying with the obtained MXenes QC values as follows: Ti3C2 = 97.5 μF/cm2, AlTi3C2NO = 141.8 μF/cm2, InTi3C2NO = 142.5 μF/cm2, and TlTi3C2NO = 100.5 μF/cm2, which are good QC values for potential electrode materials, while GaTi3C2NO = 7.5 μF/cm2. Our optical studies revealed the good interaction between the MXenes and electromagnetic waves. The MXenes exhibit good dielectric permeability, as the real parts Ꜫr(ω) of the dielectric function is ≥ 19. The imaginary parts Ꜫz(ω) of the dielectric function revealed peaks with intensity >100, which are indicative of inter-band transition.
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•DFT approach was utilized to explore properties of Ti3C2 and Ti3C2Tx, Tx = NO, and its alloys.•Results deduced show good crystal stability and an increase in the metallic property.•Spin-polarized band and DOS for the study compounds revealed an antiferromagnetic property.•Quantum capacitance of the studied compounds (MXenes) revealed an improved QC.•Optical studies have revealed a good interaction of the MXenes with electromagnetic waves.
A new stream of donor- π -acceptor (D- π -A) type arylborane-arylamine based donor contributors namely (BN1, BN2, BN3, BN4, BN5) have been drafted by substituting the terminal ...2,4,6-tris-(trifluoromethyl)phenyl groups of reference B4N2-FMes (designated as BNR in the current study) with thiophene followed by W1 (4-(5-methylthiophen-2-yl)benzothiadiazole), W2 (2-(3-methyl-5-methylene-4-oxothiazolidin-2-ylidene)malononitrile), W3 (3-methyl-5-methylene-2-thioxothiazolidin-4-one), W4 (2-methylenemalononitrile), W5 (2-cyanoacrylicaidmethylester) acceptor moieties respectively. The computational characterization was performed via reliable density functional theory at B3LYP/6–31G (d,p). The optoelectronic parameters of newly planned molecules have been cross-checked with the reference (BNR). The newly planned (BN1-BN5) conjugated macrocycles have manifested outperformed results. Amongst all, BN4 has displayed the lowest band gap (2.07 eV), highest λmax (672 nm) in dichloromethane (DCM), highest ionization potential (IP) and electron affinity (EA) owing to its functionalization with cyano (CN) containing strong electron pulling moieties. Out of all reported molecules, BN1 has explored the lowest reorganization energy (RE) value for the electron (λ- = 0.00224 eV) and hole (λ+ = 0.00266 eV) demonstrating its augmented charge transition. BN1 is characterized by the highest dipole moment (6.31 D) in DCM addressing its enhanced solubility. Amongst all, BN4 has explored the highest VOC (1.51 eV) due to its low-lying HOMO. To sum up, the thiophene bridged end-capped acceptor alteration approach has been proved persuasive in providing the gateway to devise optimistic photovoltaic materials. All currently planned donor contributors (BN1-BN5) ought to be targeted to assemble upcoming proficient organic solar cells (OSCs).
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•Five small donor molecules (BN1-BN5) have been designed for photovoltaic applications.•All the devised molecules have manifested lower band gap and higher λmax than the model (BNR).•The newly introduced acceptor moieties have displayed paramount charge mobility.
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•DIF exhibits dual fluorosolvatochromism indicating complex solvent interactions.•Catalán’s model highlights the influence of solvent acidity, basicity, and polarizability on DIF’s ...fluorosolvatochromism.•The explicit interaction between DIF and solvent molecules suggests the formation of stable hydrogen-bonded complexes.•Both the biphenyl and salicylate moieties significantly influence DIF’s fluorosolvatochromism behavior.•Understanding DIF’s behavior may aid in mitigating drug-induced toxicity.
Understanding the photochemical behavior of a photosensitive drug through its molecular properties is crucial for assessing potential phototoxicity. In this study, we examine how the molecular microenvironment influences the physicochemical and photochemical properties of Diflunisal (DIF), an organofluorine salicylate derivative drug. To elucidate the photophysical properties of DIF, we employed absorption and fluorescence spectroscopy techniques combined with various DFT-based computational methods. The solvatochromic and fluorescence behaviors of DIF were investigated employing various neat solvents of various polarity and hydrogen bonding (HB) capabilities. The molecular behavior of DIF exhibited mixed fluorosolvatochromism, where a negative fluorosolvatochromism is noted as solvent polarity increases, where DIF exhibited positive fluorosolvatochromism within the examined set of protic polar solvents. These fluorosolvatochromic behaviors suggest that a combination of factors, including solvent polarity, hydrogen bonding capacity, and specific solvation effects, influences the fluorosolvatochromic properties of DIF. To elucidate the impact of specific and non-specific interactions between DIF and solvent on the fluorosolvatochromism of DIF, we utilized Catalán’s four empirical scales model. The results revealed that the solvent’s acidity, basicity, and polarizability had approximately equivalent and notable impacts on the fluorosolvatochromic behavior of DIF. For a molecular-level explanation of the experimental spectral properties, we employed DFT and TD-DFT/B3LYP/6–31 + G(d) computational methods, incorporating the IEFPCM implicit solvation approach. It is also revealed that the negative fluorosolvatochromism of DIF is attributed to the solvent’s impact on the main electronic transition, namely HOMO → LUMO. It is revealed as well that not only the salicylate moiety is affected by the solvent, but also the biphenyl moiety can exhibit a major contribution to the observed behavior. The results presented here offer insights into the photochemical behavior of DIF within various microenvironments at the molecular level. This understanding could inform future endeavors aimed at mitigating induced toxicity and side effects of DIF.
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•The drug carrier ability of B3O3 toward Foscarnet is investigated via DFT.•The interaction is characterized by the geometric, energetic, electronic, and optical analyses.•Widely ...accepted ωB97XD/6-31+G(d,p) method of DFT is adopted for geometric analysis whereas for electronic properties B3LYP/6-31+G (d,p) method is used.•NCI and QTAIM analyses confirmed the nature of interactions.
In this study, B3O3 quantum dot is investigated via density functional theory (DFT) calculations as an antiviral drug carrier toward Foscarnet. Geometric analysis is carried out to find stable orientations of interaction between Foscarnet drug and the B3O3 quantum dot. As a result, three stable orientations are proposed. The Eint of the most stable orientation is –32.63 kcal/mol whereas the BSSE corrected energy is −26.98 kcal/mol. Noncovalent interaction index (NCI) and quantum theory of atoms in molecules (QTAIM) analyses are employed to understand the nature and the type of interactions taking place between drug and the B3O3 quantum dot. Their results indicated the presence of hydrogen bonding in the most stable complex (orientation A). The HOMO-LUMO analysis is performed to study the electronic properties of the interacting moieties. The lowest Egap is observed in case of orientation A. The value of dipole moments and chemical descriptors showed the significant activity of B3O3 quantum dot toward Foscarnet drug molecule. The overall findings from this study suggest the B3O3 quantum dot as a potential drug carrier system for antiviral drugs.
•It is shown that the tautomeric state plays a crucial role for the optical properties of azo dyes.•Currently there is no suitable DFT approach to predict the optical spectra of tautomeric azo ...dyes.•Do not neglect the tautomeric state.
In a paper of Zhu and co-workers (“Study of the electronic effect and quantitative spectra predictions of o-methoxyanilineterminated monoazonaphthols: a combined experimental and DFT study” by Guoxun Zhu, Yan Lin, Wenxian Zhou, Huacan Song and Zhengquan Li, RSC Advances, 2023, 13, 33736), the authors derived a protocol for the absorption spectra prediction is sulphonated azo naphthols assuming that they exist as single azo tautomers. However, as it is well known before and as shown by the available experimental data and the calculations, performed in this note, the studied dyes exist almost solely in hydrazone tautomeric form, which unavoidably affects the conclusions and linear relations made in the original paper. A detailed benchmarking on the spectra prediction, involving 39 density functionals (33 of them hybrid and 6 – pure) indicates that there is no a functional correctly predicting the absorption spectra of the tautomers in azo naphthols.
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•Density Functional Theory (DFT) framework has been used to explore XCdCl3 (X = Na, K, Rb and Cs) chloroperovskites.•Single-crystal elastic constant and associated mechanical ...parameters indicate that all of the compounds are mechanically stable, ductile, and soft.•All the chloroperovskites are found as semiconducting nature with an indirect bandgap energy.•Bandgap energies are preferable for visible light absorption and their application in photovoltaic technology.•Optical parameter analysis consisted of the electronic band structure analysis.
The structural, elastic, mechanical and optoelectronic properties of XCdCl3(X = Na, K, Rb and Cs) chloroperovskites have been investigated by using the Density Functional Theory (DFT) framework through the CASTEP code. The GGA, GGA-U and LDA functionals have been used to explore XCdCl3 (X = Na, K, Rb and Cs) chloroperovskites. All of the computational results of structural parameters are in good accord with the available experimental data, indicating that our work is reliable. The elastic stiffness constants Cij use the essential circumstances to show that the XCdCl3 perovskite structures are mechanically stable. The elastic modulus and other reliable features indicate the XCdCl3 chloroperovskites are mechanically ductile and soft. All the materials exhibit indirect bandgap and their bandgap energy decrease with X-site cation variation from Na to Cs. Optical conductivity and absorption for visible and ultraviolet imply their wide application in photovoltaic technology.
Theoretical calculations unveil the charge redistribution over abundant interfaces and the enhanced electronic states of Ru/RuS2 heterostructure. The resulting surface electron‐deficient Ru sites ...display optimized adsorption behavior toward diverse reaction intermediates, thereby reducing the thermodynamic energy barriers. Experimentally, for the first time the laminar Ru/RuS2 heterostructure is rationally engineered by virtue of the synchronous reduction and sulfurization under eutectic salt system. Impressively, it exhibits extremely high catalytic activity for both OER (201 mV @ 10 mA cm−2) and HER (45 mV @ 10 mA cm−2) in acidic media due to favorable kinetics and excellent specific activity, consequently leading to a terrific performance in acidic overall water splitting devices (1.501 V @ 10 mA cm−2). The in‐depth insight into the internal activity origin of interfacial effect could offer precise guidance for the rational establishment of hybrid interfaces.
Profiting from the rearranged charge density around the abundant interface and the enhanced electronic states, in acidic media, the Ru/RuS2 heterostructure exhibits prominent catalytic activity toward oxygen and hydrogen evolution reactions, and consequent remarkably high overall water splitting performance, demonstrating promising application prospect for industrial proton exchange membrane‐water electrolysis.
A magnesium‐catalyzed hydroboration of alkynes providing good yields and selectivities for a wide range of terminal and symmetrical and unsymmetrical internal alkynes has been developed. The ...compatibility with many functional groups makes this magnesium catalyzed procedure attractive for late stage functionalization. Experimental mechanistic investigations and DFT calculations reveal insights into the reaction mechanism of the magnesium catalyzed protocol.
MgBu2 proved to be an efficient catalyst for the hydroboration of terminal and internal alkynes, achieving good yields and selectivities. The compatibility with many functional groups makes the Mg‐catalyzed hydroboration of alkynes very attractive as a late stage functionalization procedure. Moreover, experimental investigations together with DFT calculations provide insight into the reaction mechanism.
•A Novel layer-stacked well designed and highly crystalline 2D MOF named as Co3(HADQ)2 MOF.•This Unique MOF features Co-N4 motifs along with pyridinic Nitrogen (total N content: 28.6 at. %) as the ...active sites for ORR.•Outclass most of the electrocatalysts with a high activity (E1/2 = 0.836 V vs. RHE, n = 3.93, and jL = 5.31 mAcm−2) in acidic media.•Exceptionally electrochemical stability up to 20,000 cycles for ORR in an acidic media at 0.29 pH.
Efficient and robust electrocatalysts for acidic Oxygen reduction reaction (ORR) is crucial for the proton exchange membrane hydrogen fuel cells. However, the current electrocatalysts suffer from the stability issues in the acidic enviorment during ORR. Herein, we introduce a new layer-stacked two-dimensional (2D) metal-organic framework (MOF), Co3(HADQ)2 (HADQ = 2,3,6,7,10,11-hexaamine dipyrazino quinoxaline), synthesized for the first time. This novel MOF material shows the extremely high conductivity of 8,385.744 S/m with extraordinary activity (E1/2 = 0.836 V vs. RHE, n = 3.93, and jL = 5.31 mAcm−2) and an exceptional stability (up to 20,000 cycles) as the electrocatalyst for ORR in an acidic media (pH = 0.29), outperforming most of the state of the art Metal-N-C and single-atom electrocatalysts for acidic ORR. Density functional theory calculations indicate that the Co-sites are the active sites. We propose that Co3(HADQ)2 is a promising model catalyst for mechanistic studies of acidic ORR, due to its well defined and tunable structure.
Nowadays, organic solar cells (OSCs) with non-fullerene electron acceptors provide the highest efficiencies among all studied OSCs. To further improve the efficiencies of fullerene-free organic solar ...cells, end-capped acceptor modification is made with strong electron withdrawing groups. In this report, we have theoretically designed five new novel Benzodithiophene core-based acceptor molecules (H1-H5) with the aim to study the possible enhancement in photophysical, optoelectronic, and photovoltaic properties of newly designed molecules. The end-capped acceptor modification of famous and recently synthesized FBDIC molecule has been made with strong electron withdrawing groups. Density functional theory and time-dependent-density functional theory are extensively used to study the structural-property relationship, optical properties and various geometrical parameters like frontier molecular orbitals alignment, excitation and binding energy, transition density matrix along with open circuit voltage, density of states and dipole moment. Commonly, low reorganization energies (hole and electron) afford high charge mobility and our all designed systems are enriched in aspect (λe = 0.0044–0.0104 eV and λh = 0.0060–0.0090 eV). Moreover, H1-H5 molecules demonstrate red-shifting in absorption spectrum (λmax = 741–812 nm) as compare to R (λmax = 728 nm). Low excitation and binding energies with low HOMO (highest occupied molecular orbital)-LUMO (lowest unoccupied molecular orbital) energy gap of H1-H5 suggested that designed molecules are better and suitable candidates for high performance organic solar cell. Results of all analysis indicate that this theoretical framework demonstrates that end-capped acceptors modification is a simple and effective alternative strategy to achieve the desirable optoelectronic properties. Therefore, H1-H5 are recommended to experimentalist for out-looking future developments of highly efficient solar cells.
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•Five new acceptor materials having benzodithiophene core are designed for organic solar cells.•The structure–property relationship, and photovoltaic properties of designed molecules is studied.•All newly designed molecules have excellent opto-electronic properties with respect to reference compound.
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