کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5425427 1395855 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Surface structure of K/Pd(1 0 0) and the effect of H coadsorption: Density functional theory calculations
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Surface structure of K/Pd(1 0 0) and the effect of H coadsorption: Density functional theory calculations
چکیده انگلیسی

We have performed density-functional theory calculations to study the atomic structure of the K/Pd(1 0 0)-p(2 × 2) and -c(2 × 2) surfaces formed at 0.25 ML and 0.5 ML, respectively. We find that K atoms prefer the hollow site with the K adsorption height 2.44 Å for p(2 × 2) and 2.50 Å c(2 × 2). The first interlayer spacing (d12) of the Pd(1 0 0) substrate appears slightly contracted from the bulk value as Δd12 = −0.8% and −0.3% for p(2 × 2) and c(2 × 2), respectively. The calculated contraction Δd12 = −0.3% for c(2 × 2) is not in accord with the expansion Δd12 = +1.3% reported by a low-energy electron diffraction (LEED) study. As the origin of this difference, a possibility of hydrogen contamination of the surface sample used in the LEED study is suggested: Our calculations show that the d12 of K/Pd(1 0 0)-c(2 × 2) increases linearly with the coverage of H coadsorption, which leads to an estimation for the H coverage of the surface sample as 0.1-0.4 ML.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface Science - Volume 601, Issue 3, 1 February 2007, Pages 852-857
نویسندگان
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