Cyano-bridged {LnIII 2 Fe III 2 } molecular squares (Ln = Gd, Tb, Dy, Ho, and Er): tuning the slow magnetic relaxation and magnetocaloric effects in zero-dimensional lanthanide Prussian blue analogues

An isostructural series of neutral cyano-bridged tetranuclear iron(III)-lanthanide(III) complexes of general formula {[Fe(htpzb)(CN)(μ-CN)2]2[Ln(dmbpy)(NO3 )2 (H2 O)]2 }·2CH3 CN·2H2 O [Ln = Gd (1), Tb (2), Dy (3), Ho (4), and Er (5); htpzb = hydrotris(pyrazolyl)borate and...