Sn(III) and Ge(III) in the thiophenolato-bridged complexes [LFeSnFeL](n+) and [LFeGeFeL](n+) (n=2, 3; L=1,4,7-(4-tert-butyl-2-mercaptobenzyl)-1,4,7-triazacyclononane)

The reaction of mononuclear [LFeIII] where L represents the trianionic liga nd 1,4,7-tris(4-tert-butyl-2-mercaptobenzyl)-1,4,7-triazacyclononane with P b(ClO4)(2). 3H(2)O in methanol affords the heterotrinuclear complex [LFePbF eL](ClO4)(2) (1). Similarly, with SnSO4 or GeI2 as starting material in an acetonitrile/water mixture and CH2Cl2, respectively, the reaction with [LFe III] yields crystalline materials of [LFeSnFeL](PF6)(2) (2a) and [LFeGeFeL] (PF6)(2) (3a) upon addition of NaPF6. Complexes 2a and 3a can be one-electr on oxidized by [Ni-III(tacn)(2)](ClO4)(3) (tacn = 1,4,7-triazacyclononane) to give [LFeSnFeL](ClO4)(3) (2b) and [LFeGeFeL](ClO4)(3) (3b). The crystal structures of [LFeSnFeL](BPh4)(2). 6CH(3)CN (2a*), [LFeSnFeL](ClO4)(3). 4.5 (CH3)(2)CO (2b*), and [LFeGeFeL](BPh4)(2). 6CH(3)CN (3a*) have been determi ned by single-crystal X-ray crystallography. The trinuclear cations consist of three face-sharing octahedra connected by six thiolato bridges affordin g the core N3Fe(mu-S)(3)M(mu-S)(3)FeN3 (M = Sn,Ge). Fe and Sn(Ge) K edge X- ray absorption spectroscopy on 2a, 2b, and 3a, 3b established that the one- electron oxidations affect exclusively the iron ions whereas the oxidation state of the central Sn(Ge) remains unaffected. Sn-119(Fe-57) Mossbauer spe ctroscopy, magnetochemistry, and EPR spectroscopy prove that both the Sn an d Ge ions in the di- and trications are trivalent since the unpaired electr on in 2b and 3b displays substantial 5s and 4s character, respectively. In contrast, in 1, an oxidation state distribution of l.s.Fe(III)Pb(II)l.s.Fe- III prevails. Complexes 1, 2a, and 3a possess a diamagnetic ground state wh ereas 2b and 3b have an S-t = 1/2 ground state.