Addition of a dithiol ligand HS(CH2)nSH (n = 2-4) to [{Rh(mu-OMe)(cod)
}2] (cod = cycloocta-1,5-diene) afforded dithiolate-bridged complexes
[{Rh2[mu-S(CH2)nS] (cod)2}x] (x = 1 or 2). These diene complexes react
with carbon monoxide to give the binuclear tetracarbonyl complexes [R
h2{mu-S(CH2)nS}(CO)4]. The crystal structures of [Rh2{mu-S(CH2)nS}(cod
)2] (n = 2 or 3) have been determined by X-ray diffraction methods. A
study of the electronic structure of the complexes by analysis of the
topology of the charge density shows that in spite of a zero formal bo
nd order between the rhodium atoms a direct metal-metal interaction ma
y be characterized.