posted on 2017-11-02, 00:00authored byXiuting Chen, Qingnuan Li, Lester Andrews, Yu Gong
Mono and diisocyanide
complexes of manganese and iron were prepared
via the reactions of laser-ablated manganese and iron atoms with (CN)2 in an argon matrix. Product identifications were performed
based on the characteristic infrared absorptions from isotopically
labeled (CN)2 experiments as compared with computed values
for both cyanides and isocyanides. Manganese atoms reacted with (CN)2 to produce Mn(NC)2 upon λ > 220 nm irradiation,
during which MnNC was formed mainly as a result of the photoinduced
decomposition of Mn(NC)2. Similar reaction products FeNC
and Fe(NC)2 were formed during the reactions of Fe and
(CN)2. All the product molecules together with the unobserved
cyanide isomers were predicted to have linear geometries at the B3LYP
level of theory. The cyanide complexes of manganese and iron were
computed to be more stable than the isocyanide isomers with energy
differences between 0.4 and 4 kcal/mol at the CCSD(T) level. Although
manganese and iron cyanide molecules are slightly more stable according
to the theory, no absorption can be assigned to these isomers in the
region above the isocyanides possibly due to their low infrared intensities.