Department of Chemistry, School of Natural Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
J Phys Chem Lett. 2023 Mar 2;14(8):2193-2200. doi: 10.1021/acs.jpclett.3c00034. Epub 2023 Feb 22.
We perform magnetization sweeps on the high-performing single-molecule magnet [Dy(Cp)][B(CF)] (Cp = CHBu-1,2,4; Bu = C(CH)) to determine the quantum tunneling gap of the ground-state avoided crossing at zero-field, finding a value on the order of 10 cm. In addition to the pure crystalline material, we also measure the tunnel splitting of [Dy(Cp)][B(CF)] dissolved in dichloromethane (DCM) and 1,2-difluorobenzene (DFB). We find that concentrations of 200 or 100 mM [Dy(Cp)][B(CF)] in these solvents increases the size of the tunneling gap compared to the pure sample, despite a similarity in the strength of the dipolar fields, indicating that either a structural or vibrational change due to the environment increases quantum tunneling rates.
我们对高性能单分子磁体 [Dy(Cp)][B(CF)]（Cp = CHBu-1,2,4；Bu = C(CH)）进行磁化强度扫描，以确定零场下地态避免交叉的量子隧穿能隙，发现其值约为 10 cm。除了纯晶态材料，我们还测量了溶解在二氯甲烷 (DCM) 和 1,2-二氟苯 (DFB) 中的 [Dy(Cp)][B(CF)] 的隧道分裂。我们发现，与纯样品相比，尽管偶极场的强度相似，但在这些溶剂中浓度为 200 或 100 mM [Dy(Cp)][B(CF)] 的情况下，隧道能隙增大，这表明由于环境的结构或振动变化导致量子隧穿速率增加。
