Interaction of rare gas dimers in the confines of a carbon nanotube

Swarm intelligence unravels the confinement effects for tiny noble gas clusters within carbon nanotubes

“…gases and small molecules on the interior and exterior walls of CNTs has been reported [17][18][19][20][21][22][23][24][25][26][27][28]. Usually, endohedral adsorption is preferred over exohedral adsorption due to the increased interactions with the walls of the CNTs in the former case [15].…”

“…Usually, endohedral adsorption is preferred over exohedral adsorption due to the increased interactions with the walls of the CNTs in the former case [15]. Among the studies probing adsorption, noble gas adsorption stands out as a forerunner for understanding the basics of physisorption [17][18][19][20][21][22]. The inertness of noble gases makes it easy to model these systems as they lack almost all chemical interactions except for the weak van der Waals interactions.…”

“…Isosteric heats and adsorption coverages of He, Ne, Ar, Kr, and Xe on endohedral and exohedral sites of CNTs as well as separation of binary and ternary mixtures of noble gases using CNTs or CNT bundles have been studied using Monte Carlo and molecular dynamics (MD) simulations [17][18][19][20]. Ab initio investigations on confined noble gas clusters are limited and are often restricted to very small cluster sizes [22,30]. Firstprinciples studies have shown that confinement brings about a reduction in internuclear distances between the noble gas atoms in the clusters when compared to those in the free clusters [22].…”

“…Ab initio investigations on confined noble gas clusters are limited and are often restricted to very small cluster sizes [22,30]. Firstprinciples studies have shown that confinement brings about a reduction in internuclear distances between the noble gas atoms in the clusters when compared to those in the free clusters [22]. For clusters of atoms and molecules, electronic structure methods turn out to be unaffordable with increas- ing cluster size and therefore we have to look for more practical alternatives for figuring out the minimum energy configurations and their adsorption energies.…”

On the directional character of orbital compression: A model study of the electric properties of LiH–(He) complexes

“…Of significant importance are also some experimental and theoretical studies demonstrating that solvation of atoms and molecules in helium or superfluid helium nanodroplets may reveal many subtle details of their electronic structure as well as spectroscopic properties [49][50][51][52][53]. Besides the fact that the helium atom proved to be a highly valuable molecular object to model the effect of orbital compression, much attention has been also devoted to understand the impact of external spatial confinement and plasma environments on its electronic structure and fundamental properties [54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72]. Particularly, it has been demonstrated that polarizability (α) and second hyperpolarizability (γ) of the spatially restricted He atom is significantly reduced in comparison to the free atom [56,57,[61][62][63][64].…”