General strategy for lanthanide coordination polymers constructed from 1,1′-ferrocenedicarboxylic acid under hydrothermal conditions

Twenty-six lanthanide coordination polymers (CPs), Ln2(fcd)2(phen)2(NO3)2 (Ln = Nd (1-Nd)), [Ln2(fcd)3(phen)2]·(CH3OH)2 (Ln = Sm (2-Sm), Eu (2-Eu), Gd (2-Gd), and Tb (2-Tb)), Ln2(fcd)2(Hfcd)2(phen)2 (Ln = La (3-La), Ce (3-Ce), Pr (3-Pr), Nd (3-Nd), Sm (3-Sm), and Gd (3-Gd)), [Ln2(fcd)3(CH3CH2OH)2(H2O)2]·H2O (Ln = La (4-La), Ce (4-Ce), Pr (4-Pr), Nd (4-Nd), Sm (4-Sm), Eu (4-Eu), Gd (4-Gd), Tb (4-Tb), Dy (4-Dy), Er (4-Er), Tm (4-Tm) and Yb (4-Yb)), and [Ln4(fcd)6(H2O)2]·nCH3CH2OH (Ln = Sm (5-Sm), Eu (5-Eu) and Tb (5-Tb)), were obtained from the reaction between 1,1′-ferrocenedicarboxylic acid (H2fcd), 1,10-phenanthroline (phen) and the corresponding lanthanide salts under hydrothermal conditions. Ln2(fcd)2(phen)2(NO3)2 (1-Nd) was constructed from discrete and neutral 0D dimeric units; [Ln2(fcd)3(phen)2]·(CH3OH)2 (2-Sm/Eu/Gd/Tb) and Ln2(fcd)2(Hfcd)2(phen)2 (3-La/Ce/Pr/Nd/Sm/Gd) were built up of 1D infinite chains, while [Ln2(fcd)3(CH3CH2OH)2(H2O)2]·H2O (4-La/Ce/Pr/Nd/Sm/Eu/Gd/Tb/Dy/Er/Tm/Yb) and [Ln4(fcd)6(H2O)2]·nCH3CH2OH (5-Sm, n = 0.33; 5-Eu, n = 0.31; 5-Tb, n = 0.30) were made up of 2D sheets. The different structures of these twenty-six CPs can be attributed to the variable conformations of fcd resulting from different reaction conditions like different counterions, ancillary ligands, temperatures, and solvents. Furthermore, the photoluminescence and magnetic properties of selected CPs have been characterized and discussed.