Crystal structures of Gd2(Cl3CCOO)6(bipy)2(H2O)2 · 4 bipy, Pr(Cl3CCOO)3(bipy)2, Nd(Cl3CCOO)3(bipy)2 and Er(Cl3CCOO)3(bipy)2(H2O)

Abstract

Abstract Single crystals of Gd2(Cl3CCOO)6(bipy)2 × (H2O)2 · 4 bipy, Pr(Cl3CCOO)3(bipy)2, Nd(Cl3CCOO)3 × (bipy)2 and Er(Cl3CCOO)3(bipy)2(H2O) have been obtained by reaction of the corresponding trichloroacetate salts with 2,2′-bipyridyl (bipy) in a water/ethanol (1:1) solution. Gd2(Cl3CCOO)6(bipy)2(H2O)2 · 4 bipy crystallizes in the monoclinic space group P21/c (no. 14, Z = 4, a = 1642.40(9) pm, b = 1227.36(10) pm, c = 2303.48(14) pm, β = 107.043(7)°). The Gd3+ ions are bridged to dimers by carboxylate groups and are surrounded by six oxygen and two nitrogen atoms. One 2,2′-bipyridyl molecule is coordinated to Gd3+, the two other ones are non-coordinated. The monomeric compounds Ln(Cl3CCOO)3(bipy)2 (Ln = Pr, Nd) are isotypic with each other and crystallize in the triclinic space group P-1 (no. 2, Z = 2, Pr: a = 989.83(8) pm, b = 1032.22(8) pm, c = 1791.56(13) pm, α = 99.312(9)°, β = 102.036(9)°, γ = 99.166(9)°; Nd: a = 990.09(7) pm, b = 1030.74(8) pm, c = 1788.70(13) pm, α = 99.393(9)°, β = 102.064(8)°, γ = 99.242(9)°). The Ln3+ atom is surrounded by six oxygen and four nitrogen atoms. A chelating coordination by the carboxylate groups is observed. There are two 2,2′-bipyridyl molecules coordinated to Ln3+. The compound Er(Cl3CCOO)3(bipy)2(H2O) crystallizes in the triclinic space group P-1 (no. 2, Z = 2, a = 1060.65(9) pm, b = 1273.35(11) pm, c = 1402.49(11) pm, α = 105.484(10)°, β = 104.504(9)°, γ = 93.712(10)°). The Er3+ ion is coordinated by four oxygen and four nitrogen atoms. There are two 2,2′-bipyridyl molecules attached to Er3+.