skip to main content

SciTech ConnectSciTech Connect

Title: Solvation of molecules in superfluid helium enhances the “interaction induced localization” effect

Atomic nuclei become delocalized at low temperatures as a result of quantum effects, whereas they are point-like in the high temperature (classical) limit. For non-interacting nuclei, the delocalization upon lowering the temperature is quantitatively described in terms of the thermal de Broglie wavelength of free particles. Clearly, light non-interacting nuclei – the proton being a prominent one – are much more delocalized at low temperatures compared to heavy nuclei, such as non-interacting oxygen having water in mind. However, strong interactions due to chemical bonding in conjunction with ultra-low temperatures characteristic to superfluid helium nanodroplets change this common picture substantially for nuclei in molecules or clusters. It turns out that protons shared in hydrogen bonds undergo an extreme “interaction induced localization” at temperatures on the order of 1 K, which compresses the protonic spatial distributions to the size of the much heavier donor or acceptor atoms, such as O or Cl nuclei, corresponding to about 0.1% of the volume occupied by a non-interacting proton at the same temperature. Moreover, applying our recently developed hybrid ab initio path integral molecular dynamics/bosonic path integral Monte Carlo quantum simulation technique to a HCl/water cluster, HCl(H{sub 2}O){sub 4}, we find that helium solvation has amore » significant additional localizing effect of up to about 30% in volume. In particular, the solvent-induced excess localization is the stronger the lesser the given nucleus is already localized in the gas phase reference situation.« less
Authors:
; ;  [1]
  1. Lehrstuhl für Theoretische Chemie, Ruhr–Universität Bochum, 44780 Bochum (Germany)
Publication Date:
OSTI Identifier:
22253272
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 14; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHEMICAL BONDS; DE BROGLIE WAVELENGTH; HEAVY NUCLEI; HELIUM; MOLECULAR DYNAMICS METHOD; MONTE CARLO METHOD; PATH INTEGRALS; PROTONS; SIMULATION; SOLVATION; SOLVENTS; STRONG INTERACTIONS; SUPERFLUIDITY