A DFT and QTAIM insight into ethylene oxide adsorption on the surfaces of pure and metal-decorated inorganic fullerene-like nanoclusters.

In this industrial era, the use of low-dimensional nanomaterials as gas sensors for environmental monitoring has received enormous interest. To develop an effective sensing method for ethylene oxide (EO), DFT computations are conducted using method ωB97X-D and B3LYP with 6-31G(d,p) basis set to evaluate the adsorption behavior of ethylene oxide gas on the surfaces of pristine, as well as Scandium and Titanium decorated B12N12, Al12N12, and Al12P12 nanocages. Several properties like structural, physical, and electronic are studied methodically to better understand the sensing behavior. Scandium-decorated aluminum phosphate and boron nitride nanocages were shown to perform better in terms of adsorption properties. The short recovery time observed in this study is beneficial for the repetitive use of the gas sensor. The Natural Bond Orbital and molecular electrostatic potential analysis demonstrated a substantial quantity of charge transfer from adsorbate to adsorbents. The bandgap alternation after adsorption shows an influence of adsorption on electronic properties. The interactions of adsorbate and adsorbents are further studied using the ultraviolet-visible predicted spectrum, and quantum theory of atoms in molecules all of which yielded promising findings.

Interaction of Anagrelide drug molecule on pristine and doped boron nitride nanocages: a DFT, RDG, PCM and QTAIM investigation.

Nowadays, a nanostructure-based drug delivery system is one of the most noticeable topics to be studied, and in this regard, boron nitride nanoclusters are promising drug carriers for targeted drug delivery systems. In this article, the interaction mechanism of Anagrelide (AG) drug with B12N12 and Al- and Ga-doped B12N12 nanocages have been investigated using DFT with B3LYP/6-31 G (d, p) method in both gas and water media. All our studied complexes are thermodynamically stable, and doped nanocage complexes have higher negative adsorption energy (EAd.) and negative solvation energy than AG/B12N12 complexes which correspond to the stability of these systems in both media. The negative highest EAd value is 64.98 kcal/mol (63.17 kcal/mol) and 65.69 kcal/mol (65.11 kcal/mol) in gas (water) media for complex F (AG/AlB11N12) and complex I (AG/GaB11N12) respectively, which refers to the highest stability of these systems. The enhanced values of dipole moment (from 12.40 (12.65) Debye to 17.21 (17.69) Debye in complex F (complex I)) also confirm their stability. The QTAIM and RDG analysis endorse the strong adsorption nature of the AG drug onto the AlB11N12, and GaB11N12 nanocages, which is consistent with the adsorption energy as chemisorption occurs for these complexes. According to the electronic properties, doped nanocages show high sensitivity that infers their promising nature for drug delivery purposes. Thus, complex F and complex I are promising drug delivery systems, and doped nanocages (AlB11N12 and GaB11N12) are better carriers than pristine nanocages for the AG drug delivery system.Communicated by Ramaswamy H. Sarma.

Conjugate mixed convection heat transfer with internal heat generation in a lid-driven enclosure with spinning solid cylinder.

The current study investigates conjugate mixed convection heat transmission with internal heat generation in a square enclosure driven by a sliding lid and a solid cylinder with a heat-conducting surface at its center. The enclosure has a stationary bottom wall that is kept at a constant hot temperature and a cold upper wall that moves consistently. The solid cylinder rotates both clockwise and counterclockwise at different angular speeds. Two-dimensional steady continuity, momentum, thermal energy equations, and boundary and interface conditions are solved using a commercial CFD tool based on the finite element method. By choosing Reynolds, Grashof, and Richardson numbers, as well as varying the rotating cylinder's speed and direction under three different scenarios incorporating volumetric heat generation, parametric modeling of the mixed convection regime is carried out. The streamline and isotherm plots are used to illustrate qualitative findings. In contrast, the average Nusselt number, normalized Nusselt number, average drag coefficient, and average fluid temperature are used to assess quantitative thermal performance measures. This study reveals that the system's thermal performance is less dependent on the solid cylinder's rotational speed and direction. It successfully depicts the heat transfer enhancement with increasing Reynolds and Grashof numbers. A thorough study of the current facts can lead to the best choice of regulating parameters.

Role of metal and anions in organo-metal halide perovskites CH3NH3MX3 (M: Cu, Zn, Ga, Ge, Sn, Pb; X: Cl, Br, I) on structural and optoelectronic properties for photovoltaic applications.

Methylammonium metal halide perovskites have recently been explored for new uses due to their unique and exciting optoelectronic properties. Their exceptional electronic properties have often been attributed to the overlap between the metal cation s and halogen p states. In this study, density functional theory calculations have been carried out based on the orthorhombic phase of the organometal trihalide perovskite CH3NH3MX3 (M: Cu, Zn, Ga, Ge, Sn, Pb; X: Cl, Br, I) to systematically investigate the effects of the metal cation and halogen anion on the structural, electronic, and optical properties for solar cell applications. The calculated lattice parameters agree well with previously obtained experimental and theoretical results. All of these perovskites are direct band gap compounds at the G symmetry point, except CH3NH3GaX3. The band gap increases from iodide to chloride and also with the metal cation size, from Ge to Pb or Cu to Zn. Furthermore, metal halide perovskites show blue shifts in their optical absorption spectra with an increase in metal cation size. Among the studied examples, CH3NH3GaBr3 and CH3NH3CuCl3 absorb a wide range of light, from UV to the visible region, and possess very unusual high dielectric constants and refractive indices. Our calculations reveal that CH3NH3SnI3, CH3NH3GeI3, and CH3NH3ZnI3 are favorable candidates for lead-free photovoltaic applications.

The computational quantum mechanical investigation of the functionalized boron nitride nanocage as the smart carriers for favipiravir drug delivery: a DFT and QTAIM analysis.

Favipiravir (FPV) is an antiviral drug used for the cure of Influenza virus, Ebola virus, Lassa virus etc. because it has excellent preventing ability of entry/exit of the virus into/from the human cells. Boron nitride nanocages have already drawn enormous attention as the delivery vehicle of various drug molecules for their nontoxicity and other lucrative properties. In this research, we have scrutinized the adsorption mechanism of FPV molecule on the exterior surface of pristine, Zn functionalized, and Ni functionalized B12N12 (BN, Zn f-BN, and Ni f-BN) nanocages by applying the DFT/QTAIM method and B3LYP/6-31G(d,p) approach. The adsorption energy (EAd) data reveal that the functionalized BN adsorbents can adsorb FPV drug very efficiently compared with the pristine adsorbent (Highest EAd is -56.40 kcal/mol for FPV adsorbed Ni f-BN complex). The reduction of the HOMO-LUMO gap up to 67.79% indicates that this drug can be detected by the produced electrical signal very promisingly in the case of f-BN nanocages. The topological parameters also validate the ability of the f-BN nanocages to adsorb the FPV molecule. The effect of the biological environment of our investigated structures has been studied by using water as a solvent, and spontaneous adsorption with high solubility is observed in our calculations. This analysis also reveals that f-BN nanocages can be a potential nanocarrier for the delivery of FPV drug molecule.Communicated by Ramaswamy H. Sarma.

A theoretical study of allopurinol drug sensing by carbon and boron nitride nanostructures: DFT, QTAIM, RDG, NBO and PCM insights.

The application of low-dimensional nanomaterials in clinical practice as efficient sensors has been increasing day by day due to progress in the field of nanoscience. In this research work, we have conducted a theoretical investigation to nominate a potential electrochemical sensor for the allopurinol (APN) drug molecule via studying the fundamental interactions of the drug molecule with two nanocages (carbon nanocage/CNC - C24 and boron nitride nanocage/BNNC - B12N12) and two nanosheets (graphene - C54H18 and boron nitride - B27N27H18) by means of the DFT B3LYP/6-31G(d,p) level of theory in both gas and water phases. The adsorption energies of APN-BNNC conjugated structures are in the range of -20.90 kcal mol-1 to -22.33 kcal mol-1, which indicates that weak chemisorption has occurred. This type of interaction happened due to charge transfer from the APN molecule to BNNC, which was validated and characterized based on the quantum theory of atoms in molecules, natural bond analysis, and reduced density gradient analysis. The highest decreases in energy gap (36.22% in gas and 26.79% in water) and maximum dipole moment (10.48 Debye in gas and 13.88 Debye in water) were perceived for the APN-BNNC conjugated structure, which was also verified via frontier molecular orbital (FMO) and MEP analysis. Also, the highest sensitivity (BNNC > BNNS > CNC > GNS) and favorable short recovery time (in the millisecond range) of BNNC can make it an efficient detector for the APN drug molecule.

The recent advancement of low-dimensional nanostructured materials for drug delivery and drug sensing application: A brief review.

In this review article, we have presented a detailed analysis of the recent advancement of quantum mechanical calculations in the applications of the low-dimensional nanomaterials (LDNs) into biomedical fields like biosensors and drug delivery systems development. Biosensors play an essential role for many communities, e.g. law enforcing agencies to sense illicit drugs, medical communities to remove overdosed medications from the human and animal body etc. Besides, drug delivery systems are theoretically being proposed for many years and experimentally found to deliver the drug to the targeted sites by reducing the harmful side effects significantly. In current COVID-19 pandemic, biosensors can play significant roles, e.g. to remove experimental drugs during the human trials if they show any unwanted adverse effect etc. where the drug delivery systems can be potentially applied to reduce the side effects. But before proceeding to these noble and expensive translational research works, advanced theoretical calculations can provide the possible outcomes with considerable accuracy. Hence in this review article, we have analyzed how theoretical calculations can be used to investigate LDNs as potential biosensor devices or drug delivery systems. We have also made a very brief discussion on the properties of biosensors or drug delivery systems which should be investigated for the biomedical applications and how to calculate them theoretically. Finally, we have made a detailed analysis of a large number of recently published research works where theoretical calculations were used to propose different LDNs for bio-sensing and drug delivery applications.