(3)-O)(2)(MU-O(2)CME)(7)(2,2'-BI-PYRIDINE)(2)]CLO4

The anhydrous form of a known tetramanganese cluster, which was previo usly isolated in its trihydrate form, has been prepared from a differe nt starting material. The new complex, bis(mu 3-oxo)-1:2:4 kappa(3) O; 2:3:4 kappa(3) O-hepta-kis(mu-acetato)-1:2 kappa(4)O:O';1:4 kappa(2)O: O';2:3 kappa(2)O:O';2:4 kappa(2)O:O';3:4 kappa(4)O:O'-bis(2,2'-bipyrid ine)-1 kappa(2)N,N';3 kappa(2)N,N'-tetramanganese perchlorate, [Mn-4(O )(2)(C2H3O2)(7)-(C10H8N2)(2)]ClO4, crystallizes in the monoclinic spac e group C2/c, in a higher symmetry compared to the previous form. A cr ystallographic twofold axis passes through the centre of the molecule. The fundamental structure of the complex clearly resembles that of th e form already reported.