Phase Transitions in Confinements: Controlling Solid to Fluid Transitions of Xenon Atoms in an On‐Surface Network

Abstract

This study reports on “phase” transitions of Xe condensates in on‐surface confinements induced by temperature changes and local probe excitation. The pores of a metal‐organic network occupied with 1 up to 9 Xe atoms are investigated in their propensity to undergo “condensed solid” to “confined fluid” transitions. Different transition temperatures are identified, which depend on the number of Xe atoms in the condensate and relate to the stability of the Xe clustering in the condensed “phase.” This work reveals the feature‐rich behavior of transitions of confined planar condensates, which provide a showcase toward future “phase‐transition” storage media patterned by self‐assembly. This work is also of fundamental interest as it paves the way to real space investigations of reversible solid to fluid transitions of magic cluster condensates in an array of extremely well‐defined quantum confinements.

Engineering quantum states and electronic landscapes through surface molecular nanoarchitectures

“…Like the previously described atomic chains in supramolecular nanogrids, this process requires thermal activation, and upon overcoming the aggregation energy barrier discrete Fe clusters in the pores are obtained. Finally, the last example addresses the adsorption of Xe noble gas atoms into the well characterized DPDI þ Cu network (Nowakowska et al, 2015Ahsan et al, 2019aAhsan et al, , 2019b. The atom-by-atom condensation leads to a maximum occupation of 12 Xe guest atoms that do not follow a single set of hierarchic filling rules, but instead adapt their structures to their neighbors (Nowakowska et al, 2015; see Fig.…”

Impacts of Surface Adsorption on Water Uptake within a Metal Organic Nanotube Material

“…The pore diameter of aquaporin channels ranges from 5 to 10 Å, and similar nanoconfinement effects have been observed in synthetic materials with channel diameters of 5–20 Å . Optimizing these nanoconfinement effects for these synthetic materials has important implications for applications such as catalysis, energy storage, and water purification. − …”

Induced Fit and Mobility of Cycloalkanes within Nanometer-Sized Confinements at 5 K

“…Each pore contains a partially localized electronic ground state giving rise to a peak in the electronic density of states (DOS) 211 meV below the Fermi level ( E F ) with both localized and nonlocalized components. As in the previously investigated Xe − cases, the interaction of the closed-shell c-alkanes with the pore containing a confined electronic state is governed by a combination of van der Waals forces and Pauli repulsion.…”

“…Cycloalkanes represent a textbook case for variable, size-dependent shape and conformational flexibility. − Their investigation inside confinements follows earlier experience gathered with porphyrins, C 60 , , and atomic Xe − being nucleated at different specific sites of on-surface coordination networks. , The molecular structures of c-alkanes are determined by the tetrahedral angle between the sp 3 carbon bonds, thus precluding planar configurations, as observed for aromatics. Different nonplanar conformations allow for a characteristic temperature-dependent dynamicity constrained by the ring-closing covalent bonds that affect the specific heat and crystal packing …”