کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5424898 1395841 2008 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Theoretical study of chemi- and physisorption processes of H2 molecules on a (1 0 0) surface of silver
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Theoretical study of chemi- and physisorption processes of H2 molecules on a (1 0 0) surface of silver
چکیده انگلیسی

A model system consisting of a cluster of 13 Ag atoms and n (n = 1, 2, 3) H2 molecules has been used to study, by ab initio methods, the structural and energetic characteristics of the chemi- and physisorption processes of H2 on a (1 0 0) surface of silver. The dissociative chemisorption of a first H2 molecule is analyzed in terms of hydrides formation and it is shown that several electronic states are interacting in the vicinity of the activation barrier leading to complex electronic processes. The energy of the physisorption interaction of the first H2 molecule for different orientations and that of further H2 molecules coming directly on top of the first chemisorbed one are determined with highly correlated wavefunctions. As for the (H2)nCu13 system, already studied with similar approaches, it is found for the (H2)nAg13 system that the physisorption energy of the second layer is enhanced by a factor close to two compared to that of the first layer due to dipolar interactions with the polarized surface. The physisorption energy of the third and further layers tends to the van der Waals H2/H2 interaction energy.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface Science - Volume 602, Issue 17, 1 September 2008, Pages 2894-2900
نویسندگان
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