Highly dealuminated and extracted ultrastable zeolite Y (US-Ex, Si:Al = 95) exhibits unique properties as support for the formation of Rh dicarbonyl and Rh dinitrosyl. The interaction of CO with Rh exchanged into US-Ex results in i˙r˙ spectra with unusually sharp (F.W.H.M. < 5 cm−1) carbonyl bands at 2118 and 2053 cm−1 and their corresponding 13CO satellites. The local structure is C2v, as verified by isotopic exchange, with a bond angle of 106° between the CO groups. The interaction of the dicarbonyl with nitric oxide yields in a fast reversible exchange of the carbonyl ligands by NO and the formation of RhI(NO)2/US-Ex with NO stretching bands at 1855 and 1780 cm−1 (F.W.H.M. < 20 cm−1). The spectra indicate the formation of well defined Rh complexes with zeolite lattice oxygens as ligands.
The formation of well defined rhodium dicarbonyls and dinitrosyls with rhodium supported on highly dealuminated zeolite Y.
ZECCHINA, Adriano;MORTERRA, Claudio;SPOTO, Giuseppe
1989-01-01
Abstract
Highly dealuminated and extracted ultrastable zeolite Y (US-Ex, Si:Al = 95) exhibits unique properties as support for the formation of Rh dicarbonyl and Rh dinitrosyl. The interaction of CO with Rh exchanged into US-Ex results in i˙r˙ spectra with unusually sharp (F.W.H.M. < 5 cm−1) carbonyl bands at 2118 and 2053 cm−1 and their corresponding 13CO satellites. The local structure is C2v, as verified by isotopic exchange, with a bond angle of 106° between the CO groups. The interaction of the dicarbonyl with nitric oxide yields in a fast reversible exchange of the carbonyl ligands by NO and the formation of RhI(NO)2/US-Ex with NO stretching bands at 1855 and 1780 cm−1 (F.W.H.M. < 20 cm−1). The spectra indicate the formation of well defined Rh complexes with zeolite lattice oxygens as ligands.
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