Two　types　of　isostructural　iron-cobalt/nickel-antimony-oxo　tartrate　cluster-based　compounds,　namely　(H3O)(Me2NH2)[M(H2O)6]2[FeII2SbIII12(mu　4-O)3(mu　3-O)8(tta)6]center　dot　6H2O　(M　=　Co　(1);　Ni　(3)),　H5/3[Co2.5FeII4/3FeIII3(H2O)13SbV1/3FeIII2/3(mu　4-O)2(mu　3-O)4SbIII6(mu　3-O)2(tta)6]center　dot　2H2O　(2)　and　H2[Ni2.25FeII1.5FeIII3(H2O)14SbV0.25FeIII0.75(mu　4-O)2(mu　3-O)4SbIII6(mu　3-O)2(tta)6]center　dot　2H2O　(4)　(H4tta　=　tartaric　acid)　were　synthesized　via　simple　solvothermal　reactions.　All　the　clusters　in　the　structures　adopt　sandwich　configurations,　that　is,　bilayer　sandwich　configuration　in　1　and　3　and　monolayer　sandwich　configuration　in　2　and　4.　Interestingly,　the　monolayer　sandwiched　compounds　2　and　4　represent　rare　examples　of　cluster-based　compounds　containing　mixed-valence　Sb(III,　V),　whose　center　of　the　intermediate　layer　is　the　co-occupied　[FexSbV1-x].　This　is　different　from　that　of　previously　reported　sandwich-type　antimony-oxo　clusters　in　which　the　center　position　is　either　occupied　by　a　transition　metal　ion　or　a　Sb(V)　alone.　Thus,　the　discovery　of　title　compounds　2　and　4　makes　the　evolution　of　center　metal　ion　more　complete,　that　is,　from　M,　MxSbV1-x　to　SbV.　All　the　title　compounds　were　fully　characterized,　and　the　photocatalysis,　proton　conduction　and　magnetism　of　compounds　2　and　4　were　studied.