Structural and photophysical properties of [(CO)

Abstract

© 2015 Elsevier Ltd. All rights reserved.The multimetallic complex [[(CO)<inf>3</inf>(phen)Re(μ-Br)Re(phen)(CO)<inf>3</inf>][(CO)<inf>3</inf>Re(μ-Br)<inf>3</inf>Re(CO)<inf>3</inf>]]·CH<inf>2</inf>Cl<inf>2</inf> was prepared by direct reaction of (Re(CO)<inf>3</inf>(THF)Br)<inf>2</inf> (THF: tetrahydrofuran) and 1,10-phenanthroline in a 1:1 ratio, followed by recrystallization in dichloromethane. The compound is an ionic salt where both, cation and anion, are bimetallic complexes. Inside both of them the Re<sup>I</sup> centers are bridged by one or three bromides respectively. The compound has an absorption band centered at 375 nm in CH<inf>2</inf>Cl<inf>2</inf>, which has been assigned to a MLCT band. Excitation at 375 nm produces luminescent emission at 608 nm. Comparison of these results with closely related rhenium complexes, in addition to Time Dependant-DFT analysis, allow us to propose the [(CO)<inf>3</inf>(phen)Re(μ-Br)Re(phen)(CO)<inf>3</inf>]<sup>+</sup> cation as main respons