TY - JOUR
T1 - Density functional modeling of reverse hydrogen spillover on zeolite-supported tetrairidium clusters
AU - Petrova, Galina P.
AU - Vayssilov, Georgi N.
AU - Rösch, Notker
N1 - Funding Information:
This work was supported by Deutsche Forschungsgemeinschaft, Fonds der Chemischen Industrie (Germany), and the National Science Fund (Bulgaria).
PY - 2007/8/27
Y1 - 2007/8/27
N2 - Stepwise reverse hydrogen spillover from bridging OH groups of the support to Ir4 clusters in a zeolite cavity was calculated exothermic, in total -421 kJ/mol for the three steps studied. In contrast to analogous modeling of supported Rh6, hydrogenation does not entail a notable extension of the metal-metal distances (here at most 2 pm). Thus, despite reverse spillover from the surrounding of the cluster, there remains a large difference, 21 ± 6 pm, between calculated and EXAFS derived Ir-Ir distances. Hydrogen migration onto Ir4 results in partial oxidation of the metal atoms, particularly those interacting with zeolite oxygen centers.
AB - Stepwise reverse hydrogen spillover from bridging OH groups of the support to Ir4 clusters in a zeolite cavity was calculated exothermic, in total -421 kJ/mol for the three steps studied. In contrast to analogous modeling of supported Rh6, hydrogenation does not entail a notable extension of the metal-metal distances (here at most 2 pm). Thus, despite reverse spillover from the surrounding of the cluster, there remains a large difference, 21 ± 6 pm, between calculated and EXAFS derived Ir-Ir distances. Hydrogen migration onto Ir4 results in partial oxidation of the metal atoms, particularly those interacting with zeolite oxygen centers.
UR - http://www.scopus.com/inward/record.url?scp=34547734444&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2007.07.056
DO - 10.1016/j.cplett.2007.07.056
M3 - Article
AN - SCOPUS:34547734444
SN - 0009-2614
VL - 444
SP - 215
EP - 219
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 4-6
ER -