Electron-transfer reactions between hexaaquochromium(II) cation

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Inorganic Chemistry> Vol. 9>N o . 9, 1970

via the -0-P-0bridges is plausible. In fact, an analogous case is that of copper(I1) formate tetrahydrate, the subnormal moment of which has been primarily attributed to superexchange through a T pathway set up by using 3d orbitals of the Cu(1I) ion and 2 p orbitals ~ of bridging HCOO- radicals.31 Magnetic exchange to a small extent between adjacent polymeric molecules is also possible.30 Such an interaction would account for the decreased demagnetization with increasing bulkiness of the ligand. In conclusion a number of Ti(III), V(III), and Cr(II1) crystalline complexes of monoacidic phosphates and phosphonates were prepared and characterized. The properties of these compounds are in favor of polymeric configurations, probably involving eight-membered (31) I