A tale of two conformers: spectroscopic evidence for halide catalysed formic acid isomerisation

Abstract

Halide-formic acid complexes have been studied utilising a combined experimental and theoretical approach. Formic acid exists as two conformers, distinguished by the relative rotation about the C-OH bond. Computational investigation...

Noncovalent chalcogen and tetrel bonding interactions: Spectroscopic study of halide–carbonyl sulfide complexes

“…In addition, the experimental data are rationalized by high-level theoretical structures of the dimer and trimer halide-carbonyl sulfide complexes, with CCSD(T) energetics extrapolated to the complete basis set limit. The relative agreement observed between experimental photoelectron peaks and the corresponding peaks determined utilizing ab initio calculations has been demonstrated in previous publications; 43,[61][62][63][64][65] this agreement allows inference of the structural motif responsible for the experimental spectra.…”

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.…”

Closing the Shell: Gas‐Phase Solvation of Halides by 1,3‐Butadiene

“…This electrostatic interaction is approximately ∼30 % more stable than the next conformer (1 trans ), where the halide bifurcates the C=C bond. Additional structures are also present in the bromide and chloride complexes (denoted 4 trans ), where the halide appends to a hydrogen on the terminal carbon similarly to previously studied halide‐formic acid complexes [13] . These structures exhibit similar bonding motifs to the halide‐propene complexes, where the bidentate structure is again the most stable complex [14] .…”

“…Additional structures are also present in the bromide and chloride complexes (denoted 4trans), where the halide appends to a hydrogen on the terminal carbon similarly to previously studied halide-formic acid complexes. [13] These structures exhibit similar bonding motifs to the halide-propene complexes, where the bidentate structure is again the most stable complex. [14] Similarly each halide structure also shows trends in their complex dissociation energy (D 0 ) values that correspond to previously studied halide-propene complexes, with the chloride complexes being the most stable and the iodide complexes being the least stable.…”