Basis set effects on the stability of the Cl2O3 isomers using B3P86 and B3LYP methods of density functional theory

Abstract

Four Cl2O3 isomers have been calculated using density functional theory with B3P86 and B3LYP functionals and various basis sets. The energy hypersurfaces of Cl2O3 are very flat and the relative energies of the isomers which have hypervalent characters such as ClOCl(O)O and ClClO3 are strongly dependent on the basis sets. The stability for Cl2O3 isomers are in the order of (1)ClOOOCl(C-s), (2)ClOOOCl(C-2), (3)ClClO3 and (4)ClOCl(O)O with ClOCl(O)O being most stable. We suggest that at least the cc-pV6Z(-ghi) basis set for Cl and the cc-pVTZ basis set for O are required to obtain reliable relative stabilities of Cl2O3 isomers with hypervalent characters. (C) 1999 Elsevier Science B.V. All rights reserved.