Elucidating the adsorption and detection of amphetamine drug by pure and doped Al12N12, and Al12P12nano-cages, a DFT study

Deciphering the electrochemical sensing capability of novel Ga12As12 nanocluster towards chemical warfare phosgene gas: insights from DFT

The applications of 3D inorganic nanomaterials in environmental and agriculture monitoring have been exploited continuously; however, the utilization of semiconductor nanoclusters, especially for detecting warfare agents, has not been fully investigated yet. To fill this gap, the molecular modelling of novel inorganic semiconductor nanocluster Ga12As12 as a sensor for phosgene gas (highly toxic for living things and the environment) is accomplished employing benchmark DFT and TD-DFT investigations. Computational tools have been applied to explore different adsorption sites and the potential sensing capability of the Ga12As12 nanoclusters. The calculated adsorption energy (-21.34 ± 2.7 kcal mol-1) for ten selected complexes, namely, Pgn-Cl@4m-ring (MS1), Pgn-Cl@6m-ring (MS2), Pgn-Cl@XY66 (MS3), Pgn-O@4m-ring (MS4), Pgn-O@XY66 (MS5), Pgn-O@XY64 (MS6), Pgn-O@Y (MS7), Pgn-planar@Y (MS8), Pgn-planar@X (MS9), and Pgn-planar@4m-ring (MS10), manifest the remarkable and excessive adsorption response of the studied nanoclusters. The explored molecular electronic properties, such as interaction distance (3.05 ± 0.5 Å), energy gap (∼2.17 eV), softness (∼0.46 eV), hardness (1.10 ± 0.01 eV), electrophilicity index (10.27 ± 0.45 eV), electrical conductivity (∼1.98 × 109), and recovery time (∼3 × 10-12 s-1) values, ascertain the elevated reactivity and an imperishable sensitivity of the Ga12As12 nanocluster, particularly for its complex MS8. QTAIM analysis exhibits the presence of a strong electrostatic bond (positive ∇2ρ(r) values), electron delocalization (ELF < 0.5), and a strong chemical bond (because of high all-electron density values). In addition, NBO analysis explores the lone pair electron delocalization of phosgene to the nanocluster stabilized by intermolecular charge transfer (ICT) and different kinds of non-covalent interactions. Also, the green region existence expressed by NCI analysis (between the nanocluster and adsorbate) stipulate the energetic and dominant interactions. Furthermore, the UV-Vis, thermodynamic analysis, and density of state (DOS) demonstrate the maximum absorbance (562.11 nm) and least excitation energy (2.21 eV) by the complex MS8, the spontaneity of the interaction process, and the significant changes in HOMO and LUMO energies, respectively. Thus, the Ga12As12 nanocluster has proven to be a promising influential sensing material to monitor phosgene gas in the real world, and this study will emphasize the informative knowledge for experimental researchers to use Ga12As12 as a sensor for the warfare agent (phosgene).

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.

Electronic band structure and density of state modulation of amphetamine and ABW type-zeolite adsorption system: DFT-CASTEP analysis

The structured abstract is combined from two parts: CONTEXT: The adsorption behavior of amphetamine (AMP) on the surface of ABW-aluminum silicate zeolite was implemented with a computational depiction. Studies of the electronic band structure (EBS) and density of states (DOS) were conducted to demonstrate transition behavior attributed to aggregate-adsorption interaction. Thermodynamic illustration of the studied adsorbate was studied to investigate the structural behavior of the adsorbate on the surface of the zeolite adsorbent. The best investigated models were assessed with adsorption annealing calculations related to adsorption energy surface. The periodic adsorption-annealing calculation model predicted a highly stable energetic adsorption system based on total energy, adsorption energy, rigid adsorption energy, deformation energy, and dE_ad/d_Ni ratio. METHODS: Cambridge sequential total energy package (CASTEP) based on density functional theory (DFT), under Perdew-Burke-Ernzerhof (PBE) basis set, was used to depict the energetic levels of the adsorption mechanism between AMP and ABW-aluminum silicate zeolite surface. DFT-D dispersion correction function was postulated for weakly interacted systems. Structural and electronic elucidations were described with geometrical optimization, FMOs, and MEP analyses. Thermodynamic parameters such as entropy, enthalpy, Gibbs free energy, and heat capacity over temperature dependence studied the conductivity behavior over localized energetic states based on Fermi level and described the disorder degree of the system.

Computational study of the interaction of the psychoactive amphetamine with 1,2-indanedione and 1,8-diazafluoren-9-one as fingerprinting reagents

In this study, we used computational methods to investigate the interaction of amphetamine (AMP) with 1,2-indanedione (IND) and 1,8-diazafluoren-9-one (DFO) so as to understand whether AMP can be detected in latent fingerprints using either of these reagents. The results show that the binding energies of AMP with IND and DFO were enhanced by the presence of amino acid from -9.29 to -12.35 kcal mol^-1 and -7.98 to -10.65 kcal mol^-1, respectively. The physical origins of these interactions could be better understood by symmetry-adapted perturbation theory. The excited state properties of the binding structures with IND demonstrate distinguishable absorption peaks in the UV-vis spectra but zero fluorescence. Furthermore, the UV-vis spectra of the possible reaction products between AMP and the reagents reveal absorption peaks in the visible spectrum. Therefore, we could predict that reaction of AMP with IND would be observable by a reddish colour while with DFO, a colour change to violet is expected. To conclude, the reagents IND and DFO may be used to detect AMP by UV-vis spectroscopy and if their reactions are allowed, the reagents may then act as a potentially rapid, affordable and easy colorimetric test for AMP in latent fingerprints without destruction of the fingerprint sample.

Adsorption behavior of mercaptopurine and 6-thioguanine drugs on the B12N12, AlB11N12 and GaB11N12 nanoclusters, a comparative DFT study

Lately, drug delivery systems established on nanostructures have become the most proficient to be studied. There are different studies suggested that the BN nanoclusters can be used as drug carriers and transport drugs in the target cell. Therefore, the interactions and adsorption behavior of Mercaptopurine (MC) and 6-thioguanine (TG) as anti-cancer drugs on the B₁₂N₁₂ (BN), AlB₁₁N₁₂ (AlBN) and GaB₁₁N₁₂ (GaBN) nanoclusters were studied by density functional theory (DFT) and quantum mechanics atoms in molecules (QMAIM) methods to find a new drug delivery system. Our results showed strong adsorption obtained in BN-MC/TG and AlBN-MC/TG complexes can be decomposed by the BN and AlBN indicating that these nanostructures are not suitable in drug efficiency of MC and TG drugs. Unlike the BN and AlBN nanoclusters, GaBN significantly makes the MC and TG drugs adsorption energetically favorable. The high solvation energy of GaBN when interacting with MC and TG drugs led it to applicability as nanocarriers for these drugs in the drug delivery systems. Furthermore, GaBN has a short recovery time for MC, and TG drugs desorption compared to BN and AlBN nanoclusters. It is predicted that the MC, and TG drugs over GaBN can be used as a drug delivery system.Communicated by Ramaswamy H. Sarma.