Two dysprosium isotopic isomers were synthesized: Et₄N[¹⁶³DyPc₂] (1) with I=5/2 and Et₄N[¹⁶⁴DyPc₂] (2) with I=0 (where Pc=phthalocyaninato). Both isotopologues are single-molecule magnets (SMMs); however, their relaxation times as well as their magnetic hystereses differ considerably. Quantum tunneling of the magnetization (QTM) at the energy level crossings is found for both systems via ac-susceptibility and μ-SQUID measurements. μ-SQUID studies of 1^(I=5/2) reveal several nuclear-spin-driven QTM events; hence determination of the hyperfine coupling and the nuclear quadrupole splitting is possible. Compound 2^(I=0) shows only strongly reduced QTM at zero magnetic field. 1^(I=5/2) could be used as a multilevel nuclear spin qubit, namely qudit (d=6), for quantum information processing (QIP) schemes and provides an example of novel coordination-chemistry-discriminating nuclear spin isotopes. Our results show that the nuclear spin of the lanthanide must be included in the design principles of molecular qubits and SMMs.

中文翻译：

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核自旋异构体：工程Et4N [DyPc2]自旋Qudit

两个镝同位素异构体来合成：的Et ₄ N [ ¹⁶³ DyPc ₂ ]（1）与我= 5/2和Et ₄ N [ ¹⁶⁴ DyPc ₂ ]（2）与我= 0（其中，PC =酞菁）。两种同位素都为单分子磁体（SMM）。但是，它们的弛豫时间以及磁滞现象差异很大。通过交流磁化率和μ-SQUID测量，发现两个系统在能级交叉处的磁化强度（QTM）量子隧穿。的μ-SQUID研究1 ^{（我= 5/2）}揭示几个核自旋驱动的QTM事件；因此确定超精细耦合和核四极分裂是可能的。化合物2 ^{（I = 0）}在零磁场下仅表现出强烈降低的QTM。1 ^{（I =} 5/2 ^）可以用作多级核自旋量子位，即qudit（d = 6），用于量子信息处理（QIP）方案，并提供了一种区分配位化学的新型核自旋同位素的实例。我们的结果表明，镧系元素的核自旋必须包含在分子量子位和SMM的设计原理中。