Molecular Modeling of Cu‑, Ag‑, and Au-Decorated Aluminum Nitride Nanotubes for Hydrogen Storage Application

The stabilities, electronic properties, and reactivities of hydrogen interactions with Cu-, Ag-, and Au-decorated aluminum nanotubes (AlNNT), H2-AlNNT, H2-Ag@AlNNT, H2-Au@AlNN T, and H2-Cu@AlNNT, for efficient hydrogen storage were investigated using density functional theory (DFT) computations at the ωB97XD/def2svp level of theory. The electron shared by H2-Ag@AlNNT, H2-Au@AlNNT, and H2-Cu@AlNNT, as well as the chemical bond created with the adsorbed hydrogen molecule, indicate chemisorption from the electron localization function (ELF) analysis, which is compatible with the adsorption energies obtained. H2-Cu@AlNNT exhibited molecular physisorption with an average hydrogen adsorption energy (Eads) of −0.027 eV, whereas H2-AlNNT, H2-Ag@AlNNT, and H2-Au@AlNNT exhibited chemisorption behavior. The molecular adsorption energies for H2-Ag@AlNNT and H2-Au@AlNNT were, respectively, −0.136 and −0.081 eV. Thus, in comparison to the other H2-adsorbed systems under investigation, the highest obtained adsorption energies were observed for these two decorated nanotube systems, respectively. H2-Ag@AlNNT and H2-Au@AlNNT are, therefore, better when compared to the other studied materials in terms of storage and adsorption of hydrogen molecules. Additionally, the negative value of Eads shows that the stated hydrogen molecule’s adsorption is thermodynamically efficient. Also, in comparison with the Department of Energy (DOE) standard, the calculated wt % values for the studied systems were found to be 6.0 and 5.8 wt % for the AlNNT and metal-decorated systems, respectively. This is quite lower than the recommended standard; however, adsorption of more hydrogen molecules and surface engineering could improve the obtained wt %. The desorption temperature was also found to be within the required range for storage materials, according to DOE. Ab initio molecular dynamics simulation also confirms surface stability. Correspondingly, the NCI analysis reveals that the nature of the connection is linked to van der Waals forces and that the hydrogen molecule interacts well with the adsorbent surfaces. These phenomenal results enshrined probably the noble metal-decorated AlN nanotube materials as efficient reservoir materials for hydrogen storage

Polypyridyl Coordinated Re(I) complexes for human tenascin-C (TNC) as an Antibreast Cancer Agent: An Intuition from Molecular Modeling and Simulations

Breast cancer continues to be the biggest cause of mortality for women worldwide, taking the lives of millions each year. As a result, scientists are now exploring the possibility of metal-based complexes as anticancer therapies. Notwithstanding, polypyridyl coordinated Re(I) complexes have demonstrated tremendous promise as cancer-fighting medications. Therefore, the intent of this research is to investigate theoretically the spectral properties, compute density functional theory (DFT), and simulate molecular docking of polypyridyl coordinated Re(I) complexes containing functionalized 2,2′-bipyridine N,N′-donor bidentate ligands: 5,5′-DiMBpy coordinated in (1a), 4,4′-DiMBpy coordinated in (2a), and 4,4′-DiMoxBp coordinated in (3a) for cancer therapy application. Intriguingly, the complex Re(2a) achieved the greatest MolDock score and H-bond energy following interactions with the target receptors utilized, followed by Re(1a) and Re(3), respectively. Thus elucidating the studied compounds to be efficient in the mitigation of breast cancer.</p

Modeling of Anthranilhydrazide (HL1) Salicylhydrazone and Its Copper Complexes Cu(I) and Cu(II) as a Potential Antimicrobial and Antituberculosis Therapeutic Candidate

Antimicrobial and antituberculosis activities of transition metal complex Cu(I) and Cu(II) from salicylhydrazone of anthranihydrazide (HL1) have been theoretically investigated using DFT methods at ωB97XD, PBEPBE, MPW1PW91, HSEH1PBE, CAM-B3LYP/6-311++G(d,p) level of theory. Owing to the fact that microbial and tuberculosis attacked still prevail despite studies reported in the literatures. This study utilized a higher theoretical model to unravel necessary information about the possible application of the HL1 and its complexes as a potential drug candidate. The results obtained reveal that the ligand (HL1) had the higher energy gap for the HES and MPW whereas, it Cu(II) complex had the least energy gap making it more reactive in the biological environment compared to its counterpart. The Natural Bond orbital (NBO) analysis reveals molecular interactions are of four kinds; LP→BD*, LP→LP*, LP*→BD*, BD*→BD*, and BD*→LP* where the higher perturbation energy was observed from BD*(C2-C3) → BD*(C4- 5) with the energy of 231.74 kcal/mol. The vibration analysis shows that the studied complexes have 32 atoms and 90 normal modes, with 20 symmetric, 7 asymmetric, 31 bending, and 32 ring torsional distribution. And their theoretical wavelength of absorption was observed to be in good agreement with experimental reported values. Cu(II) was observed with the highest dipole moment and first-order hyperpolarizability (βtotal) with corresponding values of 9.30D and 19.268 which shows its can be good for medicinal application. Molecular docking screening showed that the ligand and its complexes have better antimicrobial activities compared to antituberculosis.</p

Anti-inflammatory biomolecular activity of chlorinated-phenyldiazenyl-naphthalene-2-sulfonic acid derivatives: perception from DFT, molecular docking, and molecular dynamic simulation

In this study, two novel derivatives of naphthalene-2-sulfonic acid: 6-(((1S,5R)-3,5-dichloro-2,4,6-triazabicyclo [z3.1.0]hex-3-en-1-yl)amino)-5-((E)-phenyldiazenyl)naphthalene-2-sulfonic acid (DTPS1) and (E)-6-((4,6-dichloro-1,3,5-triazine2-yl)amino)-4-hydroxy-3-(phenyldiazenyl)naphthalene-2-sulfonic acid (DTPS2) have been synthesized and characterized using FT-IR, UV-vis, and NMR spectroscopic techniques. Applying density functional theory (DFT) at the B3LYP, APFD, PBEPBE, HCTH, TPSSTPSS, and ωB97XD/aug-cc-pVDZ level of theories for the electronic structural properties. In-vitro analysis, molecular docking, molecular dynamic (MD) simulation of the compounds was conducted to investigate the anti-inflammatory potential using COXs enzymes. Docking indicates binding affinity of −9.57, −9.60, −6.77 and −7.37 kcal/mol for DTPS1, DTPS2, Ibuprofen and Diclofenac which agrees with in-vitro assay. Results of MD simulation, indicates sulphonic group in DTPS1 has > 30% interaction with the hydroxyl and oxygen atoms in amino acid residues, but > 35% interaction with the DTPS2. It can be said that the DTPS1 and DTPS2 can induce inhibitory effect on COXs to halt biosynthesis of prostaglandins (PGs), a chief mediator of inflammation and pain in mammals. Communicated by Ramaswamy H. Sarma</p