Tailoring Dy(III) Single-Molecule Magnets Performance: Geometric and Magnetic Control via High-Intensity Oriented External Electric Fields

Single-molecule magnets (SMMs) exhibit magnetic hysteresis below a blocking temperature ( T B ), offering potential in high-density data storage and quantum computing. Practical applications, however, are limited by low T B, insufficient magnetic anisotropy, molecular instability, quantum tunneling of magnetization (QTM), and integration challenges. Traditional progress relied on serendipitous synthesis, but computational approaches like DFT and ab initio CASSCF have revealed structure–property relationships, enabling breakthroughs in lanthanide-based SMMs with T B approaching the liquid nitrogen temperature. Here, we explore oriented external electric fields (OEEFs) as a tool to address these challenges. Using DFT, DFT-based response methods, and CASSCF/RASSI-SO calculations, we systematically studied over 100 Dy(III) toy models with varying coordination numbers from 1 to 8 under electric fields and extended this to 35 Dy(III) SMMs from the literature. We establish a framework to select molecules and optimal field directions for probing under OEEFs. Our results show that OEEFs can effectively manipulate Dy(III) anisotropy, QTM, crystal field effects, and local symmetry, and can toggle SMMs on/off while enhancing magnetization reversal barriers by up to 6-fold. Additionally, OEEFs can modulate geometric isomerism, offering a strategy to fine-tune SMM properties. These findings provide guidelines for optimizing molecular magnets and open avenues for their application in quantum technologies and information storage.