Surface Chemistry in a Zeolite Matrix. Well-Defined Dinitrogen Complexes of Rhodium Supported on Dealuminated Y Zeolite

Transition metal clusters and supported species with metal–carbon bonds from first-principles quantum chemistry

“…Our simulations suggested that this band should be assigned to rhodium carbonyl species which contain additional hydrogen ligands, e.g. Rh(CO)(H 2 ) + or RhðCOÞðHÞ þ 2 , whereas the zeolite supported complex Rh(CO) + is characterized by the IR band observed at 2014 cm À1 [37], with a frequency shift relative to dicarbonyl similar to the experimental IR shift of the corresponding molecular Rh + carbonyl complexes [39].…”

“…We illustrate a combination approach, relying on spectroscopic and computational information, for the example of cationic rhodium dicarbonyl complex embedded in the cavities of dealuminated Y zeolite (DAY) [13]. This type of materials features two very sharp IR bands of CO symmetric and antisymmetric modes that confirms the formation of dicarbonyls and implies uniform location and structure of RhðCOÞ þ 2 species in zeolite [37]. The EXAFS measurements verify that the observed species are mononuclear rhodium complexes and they provide a reference for bonding distances and the number of oxygen atoms bound to a rhodium cation.…”

“…Using the same computational approach and structural models, we examined the assignment of the experimentally observed weak IR band at 2093 cm À1 assumed to correspond to Rh(CO) + species [37,38]. Our simulations suggested that this band should be assigned to rhodium carbonyl species which contain additional hydrogen ligands, e.g.…”

Identification of Neutral and Charged NxOySurface Species by IR Spectroscopy

“…Most of the cases concern Cu ϩ cations in zeolites, where a band assigned to adsorbed dinitrogen has been detected in the 2299-2290-cm Ϫ1 region [32,[129][130][131]. A strong adsorption of N 2 has been reported for Rh ϩ -exchanged zeolites [132] and Rh/Al 2 O 3 [133], where formation of geminal species has been observed. The band has been detected after adsorption of dinitrogen [130,131] or under reaction conditions [32,129].…”

Reactions of ruthenium and rhodium atoms with carbon monoxide and dinitrogen mixtures: A combined experimental and theoretical study

“…4 Among these small molecules, carbon monoxide and dinitrogen are two of the most important in transition-metal chemistry from an academic or an industrial viewpoint. 7,12 Theoretically, Rh͑CO͒͑N 2 ͒ is predicted to have a bent structure with a 2 AЈ ground state. Previous investigations exhibit that the adsorption of dinitrogen molecules on supported rhodium carbonyls produces the Rh͑CO͒͑N 2 ͒ species.…”