DFT investigation of the impact of inner-sphere water molecules on RE nitrate binding to internal pore and external surface of MCM-22.

The impact of inner-sphere water molecules on the binding of rare earth (RE) nitrates to MCM-22 aluminosilicates is analyzed. We used cluster models of MCM-22 to investigate the binding phenomena through localized-basis density functional theory (DFT) calculations. We also conducted plane-wave DFT calculations for a few selected binding configurations using the entire periodic MCM-22 unit cell to check for consistency.

Using Diglycolamide Extractants in an Imidazolium-Based Ionic Liquid for Rare Earth Element Extraction and Recovery.

Growing demands for rare earth elements (REEs) have prompted sustainability concerns worldwide. Given the need for sustainable extraction methods amidst REEs, ionic liquids (ILs) have been investigated as tunable extraction substitutes for conventional organic solvents, offering negligible volatility and diverse physical and chemical properties. Recent reports have shown that the introduction of extractants, like N,N,N',N'-tetraoctyldiglycolamide (TODGA) or N,N-dioctyldiglycolamic acid (DODGAA), into ILs can provide high selectivity and affinity for REE capture.

Dual modification to stabilize Non-IPR C fullerene: A new theoretical strategy.

The stabilization of non-IPR fullerenes for their isolation and characterization is an area of recent interest. In the present study, we have explored the stabilization techniques of C isomers via endo and exo-modifications and finally approached dual modification. A total of four isomers of C have been considered in this study; among them, one is IPR derivative (1), and the rest are non-IPR derivatives with one (2) and two (3 and 4) fused pentagon rings.

Theoretical study of gas-phase detoxication of DMMP and DMPT using ammonia-borane and its analogous compound.

The detoxication of DMMP (Dimethyl methylphosphonate) and DMPT (O, S-dimethyl methylphosphonothiolate) via hydrogenation have been investigated computationally employing density functional theory (DFT). In this present study, we aim to explore the direct molecular H assisted as well as ammonia-borane (NHBH) and 3-methyl-1,2-BN-cyclopentane (denoted as cy-AB) assisted hydrogenation pathways of DMMP and DMPT in order to detoxify them. The detoxication of DMMP has been carried out by successive elimination of two -OMe groups.

Exploration of M(100)-2×1 (M=Si, Ge) surface termination through hydrogen passivation using ethane and ammonia-borane derivatives: A theoretical approach.

Termination process of Si(100)-2 × 1 as well as Ge(100)-2 × 1 reconstructed surfaces have been explored comprehensively through the dehydrogenation of ethane and ammonia-borane and their several analogues by employing density functional theory (DFT). From our study, it is evident that the termination of Si-surface via the dehydrogenation of aforementioned ethane and NHBH derivatives is more feasible compared to Ge-surface. For ethane, the investigation shows that the substitution of non-participating hydrogens with +I group (electron donating) causes an enhancement in the kinetic and thermodynamic feasibility of the termination process, whereas the implementation of -I substituent (electron withdrawing) makes an adverse effect.

Towards a comprehensive understanding of the Si(100)-2×1 surface termination through hydrogen passivation using methylamine and methanol: a theoretical approach.

Using density functional theory, we explored the termination process of Si (100)-2 × 1 reconstructed surface mechanistically through the dehydrogenation of small molecules, considering methyl amine and methanol as terminating reagents. At first, both the terminating reagents form two types of adduct through adsorption on the Si (100)-2 × 1 surface, one in chemisorption mode and the other via physisorption, from which the dehydrogenation process is initiated. By analyzing the activation barriers, it was observed that termination of the Si-surface through the dehydrogenation is kinetically almost equally feasible using either reagent.

Identification and characterization of intramolecular γ-halo interaction in d complexes: a theoretical approach.

A mechanistic investigation to detect intramolecular M⋯X-C type interactions in d neutral and cationic complexes was carried out through a benchmark study employing different density functional methods. As γ-halogen is involved in M⋯X-C type interactions, it is denoted as a γ-halo interaction and the respective conformers are designated as halo-conformers. By analyzing the geometrical parameters of halo-conformers, it was observed that, irrespective of the nature of the metal and the halogen, the C-X bond distance increases compared to the usual C-X bond, which brings the M and X centers close enough to generate a weak interaction.

Mechanistic Insight into the Molecular TiO-Mediated Gas Phase Detoxication of DMMP: A Theoretical Approach.

The detoxication of DMMP (dimethyl methylphosphonate) mediated by molecular TiO has been investigated computationally using density functional theory (DFT). From our previous studies, it is evident that the unimolecular detoxication of OPCs (organophosphorus compounds) is kinetically unfeasible at room temperature due to the significantly high activation barrier. Thus, the aim of our work is to find out whether molecular TiO can make any significant impact on the kinetic feasibility of the detoxication processes or not.

Exploration of Unimolecular Gas-Phase Detoxication Pathways of Sarin and Soman: A Computational Study from the Perspective of Reaction Energetics and Kinetics.

A mechanistic investigation has been carried out to explore all possible gas phase unimolecular isomerization as well as decomposition pathways of toxic organophosphorus compounds (OPCs), namely, sarin (GB) and soman (GD), which are better known as nerve agents. We have identified a total of 13 detoxication pathways for sarin, where the α-H, β-H, and γ-H take part in the H-transfer process. However, for soman, due to the presence of ω-H, three additional detoxication pathways are obtained, where the ω-H is involved in the H-transfer process.

Exploration of Binding Interactions of Cu(2+) with d-Penicillamine and its O- and Se- Analogues in Both Gas and Aqueous Phases: A Theoretical Approach.

We have theoretically explored the entire binding phenomena of d-penicillamine and its O- and Se-analogues with Cu(2+) in both gas and aqueous phases. At first, a brief conformational analysis has been performed via -XH and -COOH rotations to investigate such conformers that are suitable for binding in both bidentate as well as tridentate fashions. The stability of each bidentate and tridentate complex is determined on the basis of relative energy (ΔE) and gas phase metal ion affinity (MIA) along with the bonding analysis by using atoms in molecule theory.

Hydrolysis of ammonia borane and metal amidoboranes: A comparative study.

A gas phase mechanistic investigation has been carried out theoretically to explore the hydrolysis pathway of ammonia borane (NH3BH3) and metal amidoboranes (MNH2BH3, M = Li,Na). The Solvation Model based on Density (SMD) has been employed to show the effect of bulk water on the reaction mechanism. Gibbs free energy of solvation has also been computed to evaluate the stabilization of the participating systems in water medium which directly affects the barrier heights in the potential energy surface of hydrolysis reaction.