Synthesis and structural-magnetic study of a new type of high-nuclearity metal carbonyl cluster possessing an eleven-atom Rh5Ni6 core: formation of a heterometallic core via nickel capping of a pentarhodium trigonal-bipyramidal kernel

Abstract

Equimolar reaction of (I) with (II) yields the paramagnetic Rh5Ni6 Cluster (III).

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“…To prove this assumption, we started a systematic investigation of bimetallic Ni–Rh carbonyl clusters with the aim of obtaining body‐centered cubic clusters related to either [Rh 14 (CO) 25 ] 4− ( 1 )6 or [Rh 15 (CO) 30 ] 3− ,7 but featuring Ni as the interstitial atom. Previously reported Ni–Rh carbonyl clusters—for example, [Ni 10 Rh(CO) 19 ] 3− , [Ni 9 Rh 3 (CO) 21 ] 3− , [Ni 6 Rh 3 (CO) 17 ] 3− , and [Ni 6 Rh 5 (CO) 21 ] 3− 8, 9—were obtained by reaction of [Ni 6 (CO) 12 ] 2− with 0.25–1 equiv of [{Rh(cod)Cl} 2 ] (cod=cyclooctadiene) or [{Rh(CO) 2 Cl} 2 ].…”

Hetero‐Bimetallic Ni‐Rh Carbido Carbonyl Clusters: Synthesis, Structure and 13C NMR of [Ni10Rh2C(CO)20]2–, [Ni9Rh3C(CO)20]3– and [Ni6Rh8(C2)2(CO)24]4–

“…Finally, it is noteworthy that the longitudinal relaxation times T 1 of both isomers are extremely shorter than that of the homometallic Ni carbonyl precursor [Ni 9 13 C(CO) 17 ] 6 13 C(CO) 13 ] 2-(T 1 = 1.58 s). [22] Notice that all data have been constantly measured at 9.4 Tesla and 298 K, since T 1 is field-and temperature-dependent.…”

“…This should be contrasted with the very rich chemistry of homoleptic Ni-Rh carbonyl clusters which comprises species such as [NiRh 6 (CO) 16 ] 2-, [5] [Ni 6 Rh 5 (CO) 21 ] 3-, [6] [Ni 10 Rh(CO) 19 ] 3-, [7] [Ni 9 Rh 3 -(CO) 22 ] 3-, [7] [Ni 6 Rh 3 (CO) 17 ] 3-, [7] [NiRh 13 (CO) 25 ] 5-, [8] [Ni 2 Rh 12 (CO) 25 ] 4-, [8] [Ni 5 Rh 9 (CO) 25 ] n-, [8] [NiRh 5 (CO) 14 ] 3-and [NiRh 14 (CO) 28 ] 4-. [9] At the same time, several heterobimetallic Ni-Co carbide and acetylide carbonyl clusters are known, e.g.…”

“…[9] At the same time, several heterobimetallic Ni-Co carbide and acetylide carbonyl clusters are known, e.g. [Co 2 Ni 10 C(CO) 20 ] 2-, [10] [Co 3 Ni 9 C(CO) 20 ] 2-, [10] [Co 3 Ni 9 C(CO) 20 ] 3-, [11] [Co 3 Ni 7 C 2 (CO) 15 ] 3-, [12] [Co 3 Ni 7 C 2 -(CO) 16 ] 2-, [13] [Co 6 Ni 2 C 2 (CO) 16 ] 2-. [14] Bimetallic and hetero-metallic clusters often display rather different properties than the analogous homo-metallic species, and can more easily reach higher nuclearities.…”

“…[18][19][20][21] Thus, we became interested in filling the above gap, and herein we report on the first examples of hetero-bimetallic Ni-Rh carbide and bis-acetylide carbonyl clusters, i.e. [Ni 10 Rh 2 C(CO) 20 ] 2-(3), [Ni 9 Rh 3 C-(CO) 20 ] 3- (4), and [Ni 6 Rh 8 (C 2 ) 2 (CO) 24 ] 4-(5).…”