Related Experiment Video
Updated: Jun 16, 2026

Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
Rotation of methane and silane molecules in He droplets
Hiromichi Hoshina1, Dmitry Skvortsov, Boris G Sartakov
1Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA.
Abstract:
This work studies the renormalization of the molecular moments of inertia I(G) in liquid helium. For this purpose we have measured the rotational-vibrational spectra of the nu(3) modes of a series of homologous light spherical top molecules such as CH(4), CD(4), SiH(4), and SiD(4) in He droplets. The spectra were fitted to an empirical gas phase Hamiltonian, yielding a set of spectroscopic constants. We found that the additional moment of inertia, DeltaI(He), scales approximately as square of I(G). This is in agreement with the theoretical model which assigns DeltaI(He) to coupling of molecular rotation with vibration of He in the molecular vicinity. Our results also indicate a large increase in the effective centrifugal distortion constants, which is another manifestation of the interaction of the molecular rotors with the He environment. Finally, the mechanism of the relaxation of rotational energy in liquid helium is discussed.
Related Concept Videos
Conformations of Ethane and Propane
Staggered conformation is a low energy and more stable conformation with the C-H bonds on the front carbon placed at 60°dihedral angles relative to the C-H bonds on the back carbon, leading to a reduced torsional strain. In staggered ethane, the...
Hybridization of Atomic Orbitals I
Inductive Effects on Chemical Shift: Overview
Formation of Halohydrin from Alkenes
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Radical Substitution: Halogenation of Alkanes and Alkyl Substituents
In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...

