In silico studies of the magnetic octahedral B6 − cluster—nitric oxide and [B6 −–NO]−–O2 interactions

Borophene as an carrier for mercaptopurine drug: electronic study via density-functional theory computations

CONTEXT

This paper studied MP-B36 interactions through DFT. MP molecules were observed to have a substantial tendency to be adsorbed through their N heads onto B36 at its edge, based on large adsorption energy values. The B atoms at the edges of B36 nanosheets showed higher reactivity than the internal B atoms toward MP. The electronic properties changed upon MP adsorption. The MP-B36 configurations of the highest stability underwent an energy gap reduction of 11-47%. Natural bond orbital (NBO) analysis and molecular electrostatic potential (MEP) analysis were used to evaluate the MP-B36 interaction.

METHODS

The configurations were subjected to geometric optimization at the TPSSH/6-31 + G(d) level of theory, at which frequency analysis was carried out to evaluate the stationary points. These configurations were neutral (Q = 0). The electronic properties of MP dramatically changed upon its interaction with B36 nanosheets. The stable configurations underwent an energy gap reduction, suggesting a chemical signal. The MP molecules were observed to be effectively adsorbed onto the B36 edge within aqueous phases. The MP-B36 configurations were estimated to have relatively large dipole moments. This demonstrated that MP-B36 systems were soluble and dispersed within solar media (e.g., water). It was concluded that B36 nanosheets could serve as efficient MP carriers in nanomedical drug delivery applications.

Total Electron Detachment and Induced Cationic Fragmentation Cross Sections for Superoxide Anion (O2-) Collisions with Benzene (C6H6) Molecules

In this study, novel experimental total electron detachment cross sections for O₂^- collisions with benzene molecules are reported for the impact energy range (10-1000 eV), as measured with a transmission beam apparatus. By analysing the positively charged species produced during the collision events, relative total ionisation cross sections were derived in the incident energy range of 160-900 eV. Relative partial ionisation cross sections for fragments with m/z ≤ 78 u were also given in this energy range. We also confirmed that heavier compounds (m/z > 78 u) formed for impact energies between 550 and 800 eV. In order to further our knowledge about the collision dynamics governing the fragmentation of such heavier molecular compounds, we performed molecular dynamics calculations within the framework of the Density Functional Theory (DFT). These results demonstrated that the fragmentation of these heavier compounds strongly supports the experimental evidence of m/z = 39-42, 50, 60 (u) cations formation, which contributed to the broad local maximum in the total ionisation observed from 550 to 800 eV. This work reveals the reactivity induced by molecular anions colliding with hydrocarbons at high energies, processes that can take place in the interstellar medium under various local conditions.

Quasi-planar B36 boron cluster: a new potential basis for ammonia detection

Detection of NH₃ at a trace level is nowadays of great importance. Here, we investigate the reactivity and sensitivity of a B₃₆ borophene toward NH₃ gas employing DFT calculations. The energetic results point out that the adsorption process strongly depends on the orientation of NH₃ relative to the B₃₆ sheet. An NH₃ molecule preferentially interacts via its N-head with a B atom of the B₃₆ with a change of enthalpy of - 90.5 kJ/mol at room temperature and 1 atm. Mulliken charges analysis results reveal that approximately 0.35 |e| transfers from NH₃ to the B₃₆, leaving partially positive NH₃. We found that the B₃₆ electronic properties are meaningfully sensitive to the NH₃ gas, and it may be a sign of further usage of B₃₆ as a potential NH₃ gas sensor. The density of state analysis shows that the B₃₆ gap is expressively decreased from 1.55 to 1.35 eV, increasing its electrical conductance.

Possibility of a magnetic [BN fullerene:B6 cluster]− nanocomposite as a vehicle for the delivery of dapsone

The dapsone interacting weakly with BNF (a) and functionalized BNF (b). Magnetism is induced in the molecule (c) by the BNF.