| Summary: | The reactions and photochemistry of atomic and diatomic
transition metals with methanol, water, hydrogen, and carbon
monoxide in noble gas matrices at cryogenic temperatures have
been studied with the use of Fourier Transform infrared inert
matrix spectroscopy.
Atoms and dimers of iron and cobalt reacted with methanol to
form the adducts, M(CH30H) and M2(CH30H), respectively.
M(CH30H) underwent metal insertion into the 0-H bond of methanol
to yield methoxymetal hydride, CH3OMH, with irradiation of the
matrix in the violet (400 nm < λ < 500 nm) region. Ultraviolet
(280 nm < λ < 360 nm) photolysis of the matrix rearranged
CH30MH to yield the methylmetal hydroxide species, CH3MOH.
CH30MH dissociated into carbon monoxide and hydrogen after
prolonged irradiation in the ultraviolet region.
Surprisingly, nickel atoms reacted spontaneously to insert into
the 0-H bonds of methanol and water to form CH30NiH and HONiH,
respectively. Violet photolysis caused CH30NiH to rearrange to
form methylnickel hydroxide, CH3NiOH. This is effectively a two
step process of the C-0 activation of methanol by a nickel atom. In addition to rearrangement, CH30NiH dissociates into carbon
monoxide and hydrogen with violet photolysis. Nickel dimers also
reacted spontaneously with water to form both an adduct and
insertion products.
Atomic nickel spontaneously inserts into the H-H bond of
molecular hydrogen to yield a bent nickel dihydride, NiH2, in
krypton and xenon matrices. Nickel dimers and trimers insert into
the H-H bond of hydrogen to form Nix(H)2. In addition to the
insertion products, nickel atoms, dimers, and trimers form adducts
molecularly with hydrogen to yield complexes of the form Nix(H2)y,
where x or y = 1-3.
Reactions of iron with carbon monoxide in an argon matrix
yielded the iron-carbonyl complexes, Fex(CO)y, where x = 1-3 and y
= 1-2.
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