MATRIX ISOLATION ELECTRON SPIN RESONANCE INVESTIGATION OF H$_2$$^+$, H$_4$$^+$, AND THEIR ISOTOPOMERS
Loading...
Date
2008
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
Hydrogen cluster ions are of interest as reactants in astrophysical processes and as simple models for theoretical calculations. In this work, H$_4$$^+$ and its deuterated isotopomers were isolated in a neon matrix and investigated by electron spin resonance spectroscopy. The various isotopomers were formed by mixing H$_2$, D$_2$, and HD gases with neon and depositing the mixtures onto a copper rod cooled to 2.6 K. The matrices were then x-irradiated at 60 keV for 30 minutes. Electron spin resonance spectra were recorded for H$_4$$^+$, H$_3$D$^+$, H$_2$D$_2$$^+$, HD$_3$$^+$, and D$_4$$^+$ at temperatures ranging from 2.6 K to 9 K. These isotopomers could only be formed at 2.6 K, and were very sensitive to changes in temperature. Diatomic hydrogen ions (H$_2$$^+$ and HD$^+$) were also observed at 2.6 K at low sample gas concentrations. Experimental values for the hyperfine interactions were determined by fitting the observed hyperfine structure lines with those obtained from an exact diagonalization of the spin Hamiltonian.
Description
Author Institution: Department of Chemistry, Furman University, Greenville, S.C. 29613