A computational study on the mercaptopurine drug interaction with aluminum nitride nanostructures: analyzed by Marcus theory of electron-transfer.

We analyzed the mercaptopurine adsorption on AlN nanostructures consisting of zero-dimensional nanoclusters, one-dimensional nanotubes, and two-dimensional nanosheets using calculations based on density functional theory (DFT). The adsorption energy, energy band gap, fluctuations in the energy band gap, charge transfers, and types of interactions that take place after mercaptopurine is adsorbed on the AlN nanostructures have all been calculated using DFT. The results show MP adsorption energies on AlN nanoparticles are -4.22, -5.95, and -8.70 eV. In this situation, MP molecules have been drawn to the surface due to the higher adsorption energies available on the AlN nanosheet (a process known as chemisorption). The Atoms in Molecules inquiry was conducted to learn more about and better comprehend the binding properties of the investigated AlN nanostructures utilizing mercaptopurine. Our findings indicate the mercaptopurine/AlN nanosheet bonding's electrostatic properties. Additionally, the electrical conductivity of the AlN nanostructures increases whenever mercaptopurine is adsorbed on them. This shows that the AlN nanoparticles might function as chemical sensors and offer an electrical signal in mercaptopurine. The following is the order of sensitivity: AlN nanosheet > AlN nanotube > AlN nanocluster. The outcomes indicate that the nanosheet has the most potential for mercaptopurine detection among the AlN nanostructures.Communicated by Ramaswamy H. Sarma.

Tuning the field emission and electronic properties of silicon nanocones by Al and P doping: DFT studies.

The effect of replacing an Si atom of a silicon nanocone (SiNC) by Al or P atom on its electronic and field emission properties was investigated using density functional theory calculations. Molecular electrostatic potential surface indicates that the electrons do not spread out on the surface of SiNC evenly, and they tend to accumulate more at the apex, facilitating the electron emission from this site. Replacing an Si atom of the apex of nanocone by Al and P atoms is energetically more favorable than that of the wall by about 12.0 and 8.8 kcal/mol, respectively. Both Al- and P-doping processes increase the SiNC electrical conductivity, but the electron emission from the surface of SiNC increases after the P-doping and decreases by Al- doping. The electron emission in the P-doped SiNC is predicted to be about 600 times greater than that of the pristine SiNC at room temperature. The Al- or P-doping makes the SiNC a p-type or n-type semiconductor.

N-H bond cleavage of ammonia on graphene-like B36 borophene: DFT studies.

Ammonia N-H bond cleavage at metal-free substrates has attracted great attention because of its industrial importance. Here, we investigate the dissociative adsorption of ammonia onto the surface of a B36 borophene sheet by means of density functional theory calculations. We show that the N-H bond may be broken at the edges of B36 even at room temperature, regarding the small energy barrier of 14.1-19.3 kcal mol(-1) at different levels of theory, and more negative Gibbs free energy change. Unlike basis set size, the kind of exchange correlation functional significantly affects the electronic properties of the studied systems. Also, by increasing the percentage of Hartree Fock (HF) exchange of density functionals, the activation and adsorption energies are lowered. A linear relationship between the highest occupied molecular orbital or lowest unoccupied molecular orbital of B36 borophene and the %HF exchange of functionals is predicted. Our work reveals that pure whole boron nanosheets may be promising metal-free materials in N-H bond cleavage, which would raise the potential application of these sheets.

Theoretical investigation on the selective detection of SO2 molecule by AlN nanosheets.

Theoretical calculations focused on the ability of an AlN nanosheet to detect O(3) and SO(2) molecules based on the dispersion corrected B3LYP (B3LYP-D) and B97D density functionals. Equilibrium geometries, stabilities, and the electronic properties of O(3) and SO(2) adsorptions on the surface of an AlN sheet were explored. The adsorption energies were calculated to be about -17.80 and -21.51 kcal mol(-1) at B3LYP-D level for O(3) and SO(2) corresponding to the most stable configurations, respectively. It was shown that the electrical conductance of the AlN sheet may be increased after the SO(2) adsorption, being somewhat insensitive to the O(3) adsorption. Thus, the AlN sheet may selectively detect SO(2) molecules in the presence of O(3) molecules.

DFT studies of acrolein molecule adsorption on pristine and Al-doped graphenes.

The ability of pristine graphene (PG) and Al-doped graphene (AlG) to detect toxic acrolein (C3H4O) was investigated by using density functional calculations. It was found that C3H4O molecule can be adsorbed on the PG and AlG with adsorption energies about -50.43 and - v30.92 kcal mol(-1) corresponding to the most stable configurations, respectively. Despite the fact that interaction of C3H4O has no obvious effects on the of electronic properties of PG, the interaction between C3H4O and AlG can induce significant changes in the HOMO/LUMO energy gap of the sheet, altering its electrical conductivity which is beneficial to sensor designing. Thus, the AlG may be sensitive in the presence of C3H4O molecule and might be used in its sensor devices. Also, applying an external electric filed in an appropriate orientation (almost stronger than 0.01 a.u.) can energetically facilitate the adsorption of C3H4O molecule on the AlG.

The H2 dissociation on the BN, AlN, BP and AlP nanotubes: a comparative study.

The thermodynamic and kinetic feasibility of H(2) dissociation on the BN, AlN, BP and AlP zigzag nanotubes has been investigated theoretically by calculating the dissociation and activation energies. We determined the BN and AlP tubes to be inert toward H(2) dissociation, both thermodynamically and kinetically. The reactions are endothermic by 5.8 and 3 kcal mol(-1), exhibiting high activation energies of 38.8 and 30.6 kcal mol(-1), respectively. Our results indicated that H(2) dissociation is thermodynamically favorable on both PB and AlN nanotubes. However, in spite of the thermodynamic feasibility of H(2) dissociation on PB types, this process is kinetically unfavorable due to partly high activation energy. Generally, we concluded that among the four studied tubes, the AlN nanotube may be an appropriate model for H(2) dissociation process, from a thermodynamic and kinetic stand point. We also indicated that H(2) dissociation is not homolytic, rather it takes place via a heterolytic bond cleavage. In addition, a comparative study has been performed on the electrical and geometrical properties of the tubes. Our analysis showed that the electrical conductivity of tubes is as follows: BP>AlP>BN>AlN depending on how to combine the electron rich and electron poor atoms.