Zr(0001)-(2×2)-O表面结构的分析

An Analysis for the Zr(0001)-(2×2)-O Surface Structure

LEED强度的多重散射分析,进一步确定Zr与氧作用在低覆盖量下(<1ML),形成(2×2)-O结构,是氧吸附后进入Zr表面原子层下,占据八面体空位,形成有两层氧的under layer结构,Zr表面原子层有Fcc重构。分析得到的Zt-O键距为0.232nm,而Zr-Zr间距增大为0.268nm,比原来的距离增大约4.3％,这是由于氧插入的结果。

A multiple-scattering analysis of LEED intersities has been made for Zr(0001)-(2×2)-O surface structure. The calculation results show that a moderate level of correspondence between experimental and calculated I(E) curves is reached. The optimum model is that the O atoms occupy octahedral hole sites between the Zr metal layers, oxygen incorporates into tow Zr layers with a fee-type reconstruction. LEED-determined Zr-O bond distance equal to 0. 232 nm, which is close to the value (0. 231 nm) given by X-ray diffraction for bulk ZrO. The interalyer spacing of Zr increase about 4. 3% because of the O atoms incorporation.