15min:
ELECTRON SPIN RESONONANCE (ESR) STUDIES OF NEON MATRIX-ISOLATED (HF)2- AND (DF)2- DIMER RADICAL ANIONS: VALENCE OR DIPOLE-BOUND?.

BEVAN ELLIOTT AND LON B. KNIGHT JR., Department of Chemistry, Furman University, Greenville, SC 29613.

Electron spin resonance (ESR) spectroscopic studies of the hydrogen halide dimer anion radicals (HF)2- and (DF)2- are presented. These paramagnetic species were created from the parent HF and DF gases using a rare gas microwave discharge, and trapped in neon matrices at 4 K. Whether the matrix-isolated radicals are conventional valence anions or have dipole-bound character is not fully known, but (HF)2- exists in the gas phase only as a dipole bound anion. This study of the dimer anions represents the first observation of (HF)2- outside the gas phase or isolated in any matrix, and the first observation of (DF)2- by any means.