K-2[Mo2O4(C2O4)(2)(H2O)(2)]center dot 3H(2)O

The crystal and molecular structure of dipotassium di-mu-oxo-bis[aqua(oxala to-O-1,O-2)oxomolybdenum(III)] trihydrate, K-2[Mo2O4(C2O4)(2)(H2O)(2)]. 3H( 2)O, has been determined from X-ray diffraction data. In the dimeric anion, which has approximate twofold symmetry, each Mo atom is in a distorted oct ahedral coordination, being bonded to one terminal oxo-O atom, two bridging O atoms, two O atoms from the oxalato ligand and one from the water molecu le. Bond lengths trans to the multiple-bonded terminal oxo ligand are large r than those in the cis position, confirming the trans influence as a gener ally valid rule.