ABSTRACT: The influence of synthetic conditions on the solid-state structural formation of lanthanide(iii) complexes based on a hydrazide ligand have been investigated and reported. Depending on the solvents and reaction temperatures, the reactions of hydrated Ln(NO3)3 with a benzohydrazide (bzz) ligand afforded three classes of lanthanide(iii) coordination complexes viz. [Ln(bzz)(NO3)](NO3)2 (1Ln; Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5)), [Ln(bzz)(ben)3(H2O)]·H2O (2Ln; Ln = Pr (6), Nd (7), Sm (8), Eu (9), Gd (10), Tb (11), Dy (12), Er (13)), and [Ln3(ben)3] (3Ln; Ln = Eu (14), Gd (15), Tb (16), Dy (17), Er (18), Tm (19), Yb (20), Lu (21)). Complexes 1-5 in series 1Ln were isolate
