Halide–Nitrogen Gas-Phase Clusters: Anion Photoelectron Spectroscopy and High Level ab Initio Calculations

Abstract

The gas phase anion photoelectron spectra are presented for the halide-nitrogen clusters X(-)···(N2)n, where X = Br and I and n ≤ 5. Electron binding energies for each cluster in the halide series are determined, with no evidence observed for first solvation shell closure in either series. High level ab initio calculations at the CCSD(T) level of theory are presented for the anion and neutral halogen-nitrogen complexes. For the anion species, two minima are predicted corresponding to a loosely bound C2v "T-shaped" species and to a higher energy covalently bound "triangle" C2v symmetry geometry. For the neutral species, three stationary points were located, two of which display similar form to the anion minima and a third which is linear, i.e., C∞v symmetry. The "T-shaped" geometry is a transition state linking equivalent C∞v symmetry minima. Cluster dissociation energies (D0) were determined, for both anion and neutral global minima at the CCSD(T) complete basis set limit, to be 7.8 kJ mol(-1) and 7.0 kJ mol(-1) and 3.5 kJ mol(-1) and 5.0 kJ mol(-1) for the bromine and iodine species, respectively.

Halide–propene complexes: validated DSD-PBEP86-D3BJ calculations and photoelectron spectroscopy

“…21,22 The complexes selected are the halide complexes with O 2 , N 2 , acetylene, ethene and both the syn-and anti-formic acid isomers. 17,20,[23][24][25][26][27] As these complexes have been investigated previously, starting geometries were chosen from those already optimised using ab initio methods rather than a traditional search of conformer space.…”

The Structure of CCl5– in the Gas Phase

“…Needless to say, the large difference in energy between the two detachment energies suggests that the presence of each conformer can be determined through experimental photoelectron spectroscopy. It is also noted at this point that VDEs produced from theory to predict or rationalize experimental photoelectron spectra have been used previously with great success, including those at the CCSD­(T) level of theory. − …”