MIXED VALENCE PROPERTIES OF AN NEW BINUCLEAR COMPLEX, [(EDTAH)RU-IIINCRU-II(CN)(5)](4-) AND KINETIC STUDIES OF THE AQUA SUBSTITUTION REACTION IN RU-III(EDTA)(H2O)(-) BY RU(CN)(6)(4-)

摘要

A new asymmetric mixed valence complex, K-4[(edtaH)(RuNCRuII)-N-III(CN)(5)]. 2H(2)O, has been synthesized by aqua substitution reaction of [Ru(edtaH)H2O] by K4Ru(CN)(6). Kinetic studies revealed an associative mechanism for the substitution reaction with a second order rate constant 13.8 +/- 0.6 M(-1)s(-1) at 25 degrees C and pH = 5.0. This complex shows an MMCT maximum at 682 nm in water at 25 degrees C. Thermochromism of the MMCT band has been discussed. On the basis of alpha(2) (ground state delocalisation) and H-AB (coupling integral) values this complex can be categorized as a Robin-Day class-II type complex. (C) 1997 Elsevier Science Ltd. [References: 43]