A new asymmetrically coordinated bis-trinuclear iron(III) cluster containing a {Fe3O}(7+) core has been synthesized and structurally, magnetically, and spectroscopically characterized. [Fe6Na2O2(O2CPh)(10)(pic)(4)(EtOH)(4)(H2O)(2)](ClO4)(2)center dot 2EtOH (1 center dot 2EtOH) crystallizes in the P (1) over bar space group and consists of two symmetry-related {Fe3O}(7+) subunits linked by two Na+ cations. Inside each {Fe3O}(7+) subunit, the iron(III) ions are antiferromagnetically coupled, and their magnetic exchange is best described by an isosceles triangle model with two equal (J) and one different (J') coupling constants. On the basis of the H = -2 Sigma J(ij)S(i)S(j) spin Hamiltonian formalism, the two best fits to the data yield solutions J = -27.4 cm(-1), J' = -20.9 cm(-1) and J = -22.7 cm(-1), J' = -31.6 cm(-1). The ground state of the cluster is S = (1)/(2). X-band electron paramagnetic resonance (EPR) spectroscopy at liquid-helium temperature reveals a signal comprising a sharp peak at g similar to 2 and a broad tail at higher magnetic fields consistent with the S = (1)/(2) character of the ground state. Variable-temperature zero-field and magnetically perturbed Mossbauer spectra at liquid-helium temperatures are consistent with three antiferromagnetically coupled high-spin ferric ions in agreement with the magnetic susceptibility and EPR results. The EPR and Mossbauer spectra are interpreted by assuming the presence of an antisymmetric exchange interaction with vertical bar d vertical bar similar to 2-4 cm(-1) and a distribution of exchange constants J(ij).