Binuclear metal carbonyl nitrosyls: Comparison with isoelectronic metal carbonyl derivatives

INOR 17

R. Bruce King, rbking@chem.uga.edu1, Hongyan Wang, wanghyxx@yahoo.com2, Yaoming Xie3, and Henry F. Schaefer III, hfs@uga.edu1. (1) Department of Chemistry and Center for Computational Chemistry, University of Georgia, Cedar Street, Athens, GA 30602, (2) Atomic and Molecular Physics Institute, Sichuan University, Chengdu, 610065, China, (3) Center for Computational Chemistry, University of Georgia, Athens, GA 30602

The structures of the binuclear metal carbonyl nitrosyls M2(NO)2(CO)n (M = Cr, Mn, Fe) are compared with those of the isoelectronic metal carbonyls M2(CO)n+2 (M = Mn, Fe, Co) using density functional theory with the B3LYP and PB86 functionals.  The global minimum for Cr2(NO)2(CO)7 is an unbridged structure with a Cr(NO)(CO)4 fragment linked to a Cr(NO)(CO)3 fragment through a Cr=Cr double bond.  For Cr2(NO)2(CO)6 the global minimum is a structure with two bridging CO groups, whereas the global minimum for Mn2(CO)8 is an unbridged structure.  For Cr2(NO)2(CO)5 both NO groups are bridging NO groups.  The predicted lowest energy structure for Mn2(NO)2(CO)7 has two bridging NO groups in contrast to the known structure of the isoelectronic Fe2(CO)9 with three bridging CO groups.  The structures for the unsaturated binuclear Mn2(NO)2(CO)n (n = 6, 5, 4) derivatives are similar to those of the corresponding binuclear iron carbonyls Fe2(CO)n+2 derivatives but always with a preference for bridging NO groups over bridging CO groups.

 

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Theoretical and Computational Chemistry
9:00 AM-11:20 AM, Sunday, August 19, 2007 BCEC -- 203, Oral

Division of Inorganic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007