Praseodymium complexes of 2,2 '-bipyridine; the crystal and molecular structures of Pr(bipy)(3)(NCS)(3), Pr(bipy)(2)(NO3)(3), Pr(bipy)(2)Cl-3(OH2)center dot EtOH and Pr(bipy)(S2CNEt2)(3)

The structures of Pr(biPy)(3)(NCS)(3), Pr(bipy)(2)(NO3)(3), Pr(bipy)(2)Cl-3(OH2).EtOH and Pr(bipy)(S2CNEt2)(3) are reported. Pr(biPY)(3)(NCS)(3) has a monomeric structure with three N-bonded thiocyanates and three bidentate bipyridyl ligands, giving nine-coordinate praseodymium. Praseodymium is eight-coordinate in Pr(bipy)(2)Cl-3(OH2).EtOH and in Pr(bipy)(S2CNEt2)(3) whilst Pr(bipy)(2)(NO3)(3) is isostructural with the La, Nd and Lu analogues, having three bidentate nitrates and two bipyridyl ligands, affording 10-coordinate praseodymium. Factors affecting bond lengths in the compounds are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.