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Title: [Ni 30 S 16 (PEt 3 ) 11 ]: an open-shell nickel sulfide nanocluster with a “metal-like” core
Reaction of [Ni(1,5-cod) 2 ] (30 equiv.) with PEt 3 (46 equiv.) and S 8 (1.9 equiv.) in toluene, followed by heating at 115 °C for 16 h, results in the formation of the atomically precise nanocluster (APNC), [Ni 30 S 16 (PEt 3 ) 11 ] (1), in 14% isolated yield. Complex 1 represents the largest open-shell Ni APNC yet isolated. In the solid state, 1 features a compact “metal-like” core indicative of a high degree of Ni–Ni bonding. Additionally, SQUID magnetometry suggests that 1 possesses a manifold of closely-spaced electronic states near the HOMO–LUMO gap. In situ monitoring by ESI-MS and 31 P{ 1 H} NMR spectroscopy reveal that 1 forms via the intermediacy of smaller APNCs, including [Ni 8 S 5 (PEt 3 ) 7 ] and [Ni 26 S 14 (PEt 3 ) 10 ] (2). The latter APNC was also characterized by X-ray crystallography and features a nearly identical core structure to that found in 1. This work demonstrates that large APNCs with a high degree of metal–metal bonding are isolable for nickel, and not just the noble metals.  more » « less
Award ID(s):
1764345 1920299
NSF-PAR ID:
10339776
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Chemical Science
Volume:
13
Issue:
18
ISSN:
2041-6520
Page Range / eLocation ID:
5171 to 5175
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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