Tuning the properties of atomic crystals in the two-dimensional (2D) limit is synthetically challenging, but critical to unlock their potential in fundamental research and nanotechnology alike. 2D crystals assembled using superatomic blocks could provide a route to encrypt desirable functionality, yet strategies to link the inorganic blocks together in predetermined dimensionality or symmetry are scarce. Here, we describe the synthesis of anisotropic van der Waals crystalline frameworks using the designer superatomic nanocluster Co 3 (py) 3 Co 6 Se 8 L 6 (py = pyridine, L = Ph 2 PN(Tol)), and ditopic linkers. Post-synthetically, the 3D crystals can be mechanically exfoliated into ultrathin flakes (8 to 60 nm), or intercalated with the redox-active guest tetracyanoethylene in a single-crystal-to-single-crystal transformation. Extensive characterization, including by single crystal X-ray diffraction, reveals how intrinsic features of the nanocluster, such as its structure, chirality, redox-activity and magnetic profile, predetermine key properties of the emerging 2D structures. Within the nanosheets, the strict and unusual stereoselectivity of the nanocluster's Co edges for the low symmetry (α,α,β) isomer gives rise to in-plane structural anisotropy, while the helically chiral nanoclusters self-organize into alternating Δ- and Λ-homochiral rows. The nanocluster's high-spin Co edges, and its rich redox profile make themore »
Inorganic clusters as metalloligands: ligand effects on the synthesis and properties of ternary nanopropeller clusters
Redox-active multimetallic platforms with synthetically addressable and hemilabile active sites are attractive synthetic targets for mimicking the reactivity of enzymatic co-factors toward multielectron transformations. To this end, a family of ternary clusters featuring three edge metal sites anchored on a [Co 6 Se 8 ] multimetallic support via amidophosphine ligands are a promising platform. In this report, we explore how small changes in the stereoelectronic properties of these ligands alter [Co 6 Se 8 ] metalloligand formation, but also substrate binding affinity and strength of the edge/support interaction in two new ternary clusters, M 3 Co 6 Se 8 L 6 (M = Zn, Fe; L (−) = Ph 2 PN (−)i Pr). These clusters are characterized extensively using a range of methods, including single crystal X-ray diffraction, electronic absorption spectroscopy and cyclic voltammetry. Substrate binding studies reveal that Fe 3 Co 6 Se 8 L 6 resists coordination of larger ligands like pyridine or tetrahydrofuran, but binds the smaller ligand CN t Bu. Additionally, investigations into the synthesis of new [Co 6 Se 8 ] metalloligands using two aminophosphines, Ph 2 PN(H) i Pr (L H ) and i Pr 2 PN(H) i Pr, led to the synthesis and more »
- Award ID(s):
- 1944843
- Publication Date:
- NSF-PAR ID:
- 10212253
- Journal Name:
- Dalton Transactions
- Volume:
- 49
- Issue:
- 45
- Page Range or eLocation-ID:
- 16464 to 16473
- ISSN:
- 1477-9226
- Sponsoring Org:
- National Science Foundation
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