hrvatski

Utjecaj reakcijskih uvjeta na dobivanje polioksalatomolibdata različite nuklearnosti

The main driving forces responsible for the formation of polyoxomolybdates (POMos) are various interactions and self-assembly processes between [MoO4] 2- anions. Most common synthetic methods involve acidification of aqueous solutions containing [MoO4] 2- anion or neutralization of the molybdenum trioxide solution [1]. The main goal of modern POMo studies is the synthesis of materials with specific properties and applications. In our previous research we have postulated that hydrogen bonding capacity of counterions and reaction conditions greatly influence the condensation processes in POMo chemistry [2, 3] which led us to use [Co(C2O4) (NH3)4] + and [Co(CO3)(NH3)4] + as a counterion in POMo synthesis from [MoO4] 2- units in the presence of different molar ratios of oxalic acid. Solutionbased synthesis reactions were performed in an aqueous medium at room temperature or at 110°C. Depending on the reaction conditions (method, pH, concentration of oxalic acid), following products were isolated and characterized: [Co(C2O4) (NH3)4]2[MoO4], [CoIII(C2O4) (NH3)4]2[CoII(C2O4)2(H2O)2], Na3[Co(C2O4) (NH3)4][Mo2O4(μ-O)2(C2O4)2], [Co(C2O4) (NH3)4]4[Mo3O6(μ-O)2(C2O4)3(H2O)2] and [Co(C2O4)(NH3)4]2[Mo2O5(C2O4)2(H2O)2].

kobalt ; kompleksne soli ; molibden ; polioksometalati

nije evidentirano

engleski

The influence of reaction conditions on obtaining polyoxalatomolybdates of various nuclearity

The main driving forces responsible for the formation of polyoxomolybdates (POMos) are various interactions and self-assembly processes between [MoO4] 2- anions. Most common synthetic methods involve acidification of aqueous solutions containing [MoO4] 2- anion or neutralization of the molybdenum trioxide solution [1]. The main goal of modern POMo studies is the synthesis of materials with specific properties and applications. In our previous research we have postulated that hydrogen bonding capacity of counterions and reaction conditions greatly influence the condensation processes in POMo chemistry [2, 3] which led us to use [Co(C2O4) (NH3)4] + and [Co(CO3)(NH3)4] + as a counterion in POMo synthesis from [MoO4] 2- units in the presence of different molar ratios of oxalic acid. Solutionbased synthesis reactions were performed in an aqueous medium at room temperature or at 110°C. Depending on the reaction conditions (method, pH, concentration of oxalic acid), following products were isolated and characterized: [Co(C2O4) (NH3)4]2[MoO4], [CoIII(C2O4) (NH3)4]2[CoII(C2O4)2(H2O)2], Na3[Co(C2O4) (NH3)4][Mo2O4(μ-O)2(C2O4)2], [Co(C2O4) (NH3)4]4[Mo3O6(μ-O)2(C2O4)3(H2O)2] and [Co(C2O4)(NH3)4]2[Mo2O5(C2O4)2(H2O)2].

cobalt ; complex salt ; molybdenum ; polioxometalates

nije evidentirano