I. Alkorta et al., CHARGE-TRANSFER COMPLEXES BETWEEN DIHALOGEN COMPOUNDS AND ELECTRON-DONORS, The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory, 102(46), 1998, pp. 9278-9285
A theoretical study of the charge-transfer complexes formed by dihalog
en compounds (F-2, Cl-2, Br-2, FBr, FCl, and ClBr) and electron donors
(FH, OH2, NH3, CO, NCH, and C2H2) has been carried out. The geometrie
s, energies, and electronic and spectroscopic properties of these comp
lexes have been compared with the corresponding properties of the hydr
ogen bonded complexes of FH with the same electron donors. The hybrid
HF-DFT, B3LYP, and second-order Mollet-Plesset perturbation, MP2, meth
ods have been used. The properties analyzed include geometry, energy,
electron distribution using the atoms in molecules (AIM) methodology,
and spectroscopic constants of the complexes and monomers. Similaritie
s in the variations of the geometries, in the trends in the interactio
n energetic, and in the topological electron density characteristics b
etween the properties of the HE complexes and the dihalogen charge-tra
nsfer systems are pointed out. The main differences correspond to the
variation trend of the atomic properties and the NMR shielding when go
ing from the monomers to the complexes.