Unsaturation in binuclear heterometallic carbonyls: the cyclopentadienyliron manganese carbonyl CpFeMn(CO)n system as a hybrid of the Cp2Fe2(CO)n and Mn2(CO)n systems

The manganese carbonyl cyanides Mn(CO)n(CN) and Mn2(CO)n(CN)2 have been investigated by density functional theory. The lowest energy structure for Mn(CO)5(CN) is found to be the experimentally known C-bonded cyanide. The experimentally unknown N-bonded Mn(CO)5(NC) lies ~60 kJ mol–1 above its cyanide isomer. The Mn(CO)4(CN) isomers are obtained by removal of a CO group in various ways from Mn(CO)5(CN) or Mn(CO)5(NC). Three structures, cyanide Mn(CO)3(CN), isocyanide Mn(CO)3(NC), and Mn(CO)3(η2-CN), are found for the tricarbonyl. All low-energy binuclear Mn2(CO)n(CN)2 structures have two end-to-end bridging CN groups. These two η2-CN bridges can be oriented in the same or opposite directions. The Mn2(CO)7(CN)2 structures of this type can be derived from these Mn2(CO)8(CN)2 structures by removal of a CO group with relatively little change in the remainder of the structure. These low-energy Mn2(CO)n(CN)2 structures (n = 8, 7) are very different from the previously studied isoelectronic Cr2(CO)n+2 structures in which low-energy end-to-end CO bridged structures are not found.

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Heterobimetallic Chromium Manganese Carbonyl Nitrosyls: Comparison with Isoelectronic Homometallic Binuclear Chromium Carbonyl Nitrosyls and Manganese Carbonyls

Inorganics ◽

10.3390/inorganics7100127 ◽

2019 ◽

Vol 7 (10) ◽

pp. 127

Author(s):

Guoliang Li ◽

Limei Wen ◽

R. Bruce King

Keyword(s):

Density Functional Theory ◽

Electron Donor ◽

Density Functional ◽

Manganese Atom ◽

Chromium Atom ◽

Electron Configuration ◽

Single Bond ◽

Functional Theory ◽

Chromium Carbonyl ◽

Manganese Carbonyl

The heterometallic chromium-manganese carbonyl nitrosyls CrMn(NO)(CO)n (n = 9, 8) have been investigated by density functional theory. The lowest energy CrMn(NO)(CO)9 structures have unbridged staggered conformations with a ~2.99 Å Cr–Mn single bond similar to the experimental and lowest energy structures of the isoelectronic Mn2(CO)10 and Cr2(NO)2(CO)8. A significantly higher energy CrMn(NO)(CO)9 isomer has a nearly symmetrical bridging nitrosyl group and a very weakly semibridging carbonyl group. The two lowest energy structures of the unsaturated CrMn(NO)(CO)8 have a five-electron donor bridging η2-µ-NO nitrosyl group or a four-electron donor bridging η2-µ-CO group, as well as a Cr–Mn single bond of length ~2.94 Å. The next higher energy CrMn(NO)(CO)8 structure has exclusively terminal CO and NO ligands and a shorter Cr–Mn single bond of ~2.85 Å, suggesting an 18-electron configuration for the manganese atom and a 16-electron configuration for the chromium atom indicated by a vacant coordination site nearly perpendicular to the Cr–Mn bond.

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Doping effects on the geometric and electronic structure of tin clusters

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05124d ◽

2019 ◽

Vol 21 (44) ◽

pp. 24478-24488 ◽

Cited By ~ 1

Author(s):

Martin Gleditzsch ◽

Marc Jäger ◽

Lukáš F. Pašteka ◽

Armin Shayeghi ◽

Rolf Schäfer

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Density Functional ◽

Beam Deflection ◽

Functional Theory ◽

Doping Effects ◽

Depth Analysis ◽

Trajectory Simulations

In depth analysis of doping effects on the geometric and electronic structure of tin clusters via electric beam deflection, numerical trajectory simulations and density functional theory.

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