Barrierless proton transfer across weak CH⋯O hydrogen bonds in dimethyl ether dimer

• DOI: 10.1063/1.4914456
• Publication Date: 2015-03-17T18:27:06Z
• Authors: Bruce L. Yoder; Ksenia B. Bravaya; Andras Bodi; Adam H. C. West; Bálint Sztáray; Ruth Signorell
• Keywords: Dimethyl ether; Isotopologue

We present a combined computational and threshold photoelectron photoion coincidence study of two isotopologues dimethyl ether, (DME − h6)n d6)n n = 1 2, in the 9–14 eV photon energy range. Multiple isomers neutral ether dimer were considered, all which may be present, exhibited varying C–H⋯O interactions. Results from electronic structure calculations predict that them undergo barrierless proton transfer upon photoionization to ground state cation. In fact, found relax same radical cation structure. The lowest dissociative channel leads CH3OHCH3+ by loss CH2OCH3 with 0 K appearance 9.71 ± 0.03 9.73 for h6)2 deuterated d6)2, respectively. spectrum band is broad exhibits no vibrational Dimerization results 350 meV decrease valence energy, 140 maximum, thus an almost twofold increase width, compared DME d6 monomer.