Influence of porphyrin meso-attached substituent on the SMM behavior of dysprosium(III) double-deckers with mixed tetrapyrrole ligands

摘要

Three sandwich-type neutral unprotonated mixed (phthalocyaninato)(porphyrinato) dysprosium(III) double-decker complexes Dy(Pc)(Por) [ Por = TCPP, TPP, TBPP; Pc = unsubstituted phthalocyaninate, TCPP = 5,10,15,20-tetrakis(4-cyanophenyl) porphyrinate, TPP = 5,10,15,20-tetrakis(phenyl) porphyrinate, TBPP = 5,10,15,20-tetrakis[(4-tert-butyl) phenyl] porphyrinate] (1-3) have been designed, prepared, and structurally studied. Systematic and comparative studies reveal the slow relaxation of magnetization under both zero and applied dc field for all three double-deckers, indicating their SMM nature. Stronger quantum tunneling of magnetization (QTM) observed for 3 in comparison with its two counterparts 1 and 2 with similar coordination geometry shows the influence of substituent at the meso-attached phenyl moieties on the magnetic properties.