Numéro
J. Phys. IV France
Volume 03, Numéro C4, Septembre 1993
4th International Workshop on Positron and Positronium Chemistry
Page(s) C4-113 - C4-119
DOI http://dx.doi.org/10.1051/jp4:1993413
4th International Workshop on Positron and Positronium Chemistry

J. Phys. IV France 03 (1993) C4-113-C4-119

DOI: 10.1051/jp4:1993413

Further results on the relationship between the rate constants of o-Ps into p-Ps conversion and the electron delocalization in 3d complexes

A.L. FANTOLA LAZZARINI, E. LAZZARINI and M. MARIANI

Dipartimento Ingegneria Nucleare, CeSNEF Politecnico di Milano, Via Ponzio 34/3, 20133 Milano, Italy


Abstract
The ortho into para-positronium conversion reactions promoted by the paramagnetic complexes formed with ethylenediaminetetraacetic acid (H4EDTA) by Mn(II), Fe(II), Co(II), Ni(II) ions were studied at various temperatures. The results are discussed together with those previously obtained for the Cr(III) and Cu(II) complexes with the same ligand. It was found that the rate constants, kSE, are larger for complexes : A) whose 3d inter-electronic repulsion parameter attains smaller values ; and B) for which spin orbit coupling occurs. These findings give further support to our proposal that the o-Ps into p-Ps conversion reaction may be used to investigate the electron delocalization in paramagnetic 3d complexes.



© EDP Sciences 1993