Collect. Czech. Chem. Commun. 2010, 75, 243-256
https://doi.org/10.1135/cccc2009532
Published online 2010-03-04 11:46:37

The nature of the bond-length change upon molecule complexation

Weizhou Wang*, Yu Zhang and Baoming Ji

College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, China

Abstract

The nature of the bond-length change upon molecule complexation has been investigated at the MP2/aug-cc-pVTZ level of theory. Our results have clearly shown that the X–Y bond-length change upon complex formation is determined mainly by the electrostatic attractive interaction and the charge-transfer interaction. In the case of strongly polar bond, the electrostatic interaction always causes bond elongation while in the case of weakly polar bond it causes bond contraction. The charge-transfer interaction generally results in the X–Y bond elongation; either it is a more polar bond or it is a less polar bond. Employing this simple “electrostatic interaction plus charge-transfer interaction” explanation, we explained and predicted many interesting phenomena related to the bond-length change upon molecule complexation. In addition, the difference between the origin of the bond-length change upon hydrogen-bonded complex formation and the origin of the bond-length change upon halogen-bonded complex formation was also discussed.

Keywords: Bond-length change; Hydrogen bond; Halogen bond; Electrostatic interaction; Charge-transfer interaction; Ab initio calculations.

References: 22 live references.