969p-oxo groups (2.050 A) is 0.047 shorter than the average trans distance (2.097 A). This elongation trans to the p-oxo groups for the Mn(IV) ion is often observed for oxo-bridged species,22 including 1. Unlike the situation for 1 and 3, mixed-valence
complexes 2 and [(TACN)Mn(p-O)2(p-OAc)Mn(TACN)]3+(4)Iza do not have distinguishable Mn(II1) and Mn(IV) ions. Cyclic voltammetry of 3 reveals a quasi-reversible redox wave with E, = 0.87 V, E, = 0.79 V, and E l / 2 = 0.83 V (vs Ag/Ag+), corresponding to the 111, IV/IV,IV couple and a wave at E , = 0.15 V, E, = -0.02 V, and E I l 2 = 0.085 V, due to the III,IV/III,III couple.23 The former couple for 1, and 2, lies at significantly higher values: E I l 2 = 1.25 and 1.26 V, respectively.' The EPR spectrum of 3, displayed in Figure 2, bears a remarkable resemblance to that for a recently reported species suspected of being a peroxy-bridged Mn"Mn"' complex.24 Preliminary simulations for the 16-line pattern in Figure 2 yielded spectral parameters A, = 150 X IO4 cm-I and A2 = 78 X lo4 cm-I, in good agreement Synthesis and Structures of [(C,H,),P],[M(CO),Te,] (M = Cr, W), Containing a Polytelluride Ligand Derived from a Soluble Zintl Anion 13007-92-6; W(CO),, 14040-1 1-0; K2Te3, 67488-76-0; K2Te,, 78547-42-9; K2Te,, 112817-28-4; Mo(CO),, 13939-06-5. Supplementary Material Available: Tables of atomic coordinates and isotropic temperature factors, cation and solvent distances and angles, anisotropic temperature factors, and hydrogen atom parameters (1 7 pages); a table of observed and calculated structure factors (63 pages). Ordering information is given on any current masthead page. (22) Schrobilgen G. J.; Bjorgvinnson, M., in press.
