Nanoscale Quantum Solvation of para-H$_2$ around the Linear OCS Molecule inside $^4$He Droplets

TL;DR

This paper investigates how para-H$_2$ molecules arrange themselves around an OCS molecule inside $^4$He droplets at low temperatures, revealing helium's minimal impact on structure except at M=6, with implications for superfluidity and spectroscopy.

Contribution

It provides a detailed microscopic analysis of quantum solvation structures of para-H$_2$ around OCS in helium droplets, highlighting helium's limited influence on cluster configurations.

Findings

Helium has negligible effect on small and large clusters.

Helium modifies structure at M=6 clusters.

Results inform superfluidity onset and spectroscopic behavior.

Abstract

We present a microscopic analysis of the quantum solvation structures of para-H$_2$ around the OCS molecule when embedded in low temperature $^4$He droplets. The structures of clusters containing M=5 and 6 para-H$_2$ molecules are compared with corresponding structures for M=1 (OCS-H$_2$ complex) and M=17 (a full solvation shell), as well as with the clusters in the absence of helium. We find that the helium has negligible effect on the structures for the small and large OCS(H$_2$)$_M$ clusters, but that it modifies the cluster structure for M=6. We discuss implications of these results for the onset of superfluidity in the solvating hydrogen shell and for spectroscopic measurements.