Electrospray Ionization Mass Spectrometry Insights into the Assembly of Lanthanide-Containing Clusters

Atomically precise metal clusters with well-defined crystal structures have emerged as a rapidly growing field within coordination and materials chemistry. Among them, lanthanide-containing clusters (LCCs) are particularly notable for their aesthetically pleasing architectures and intriguing properties. Achieving precise synthesis and accurate structural characterization of these clusters is crucial for unlocking their potential applications. Mass spectrometry (MS), particularly electrospray ionization mass spectrometry (ESI-MS), has proven to be a powerful tool, providing exceptional sensitivity and clarity in revealing the formation mechanisms and structural details of metal clusters. In this Account, we explore the synthesis, characterization, and assembly mechanisms of LCCs utilizing ESI-MS. We begin by tracing the historical development of LCCs, emphasizing the critical role of single-crystal X-ray diffraction in structural confirmation and the challenges associated with it. We then discuss the application of ESI-MS in characterizing LCCs, highlighting how this technique can monitor the formation processes of LCCs and determine their molecular weights and charge states. We introduce the mass difference fingerprint of isomorphism (MDFI) method, which can facilitate rapid analysis of LCCs’ mass spectrometry data. Furthermore, we discuss the state of LCCs in solution and the challenges in their characterization. By utilizing ESI-MS, we enhance the understanding of the assembly mechanisms of LCCs and propose new strategies for designing and synthesizing new LCCs with tailored structures and functions. Looking forward, the ESI-MS method will play increasingly significant roles in LCC research. The continued development of these technologies will deepen the understanding of the structure–property relationships. With the ongoing convergence of computational chemistry and information science, we anticipate more precise design and synthesis of LCCs, leading to broader applications in magnetism, optics, and catalysis.