Surface Core-Level Shifts and Atomic Coordination at a Stepped W(110) Surface

Authors

D. Mark Riffe, Utah State UniversityFollow
B. Kim
J. L. Erskine
N. D. Shinn

Document Type

Article

Journal/Book Title/Conference

Physical Review B

Volume

50

Issue

19

Publication Date

11-15-1994

First Page

11481

Last Page

14488

Abstract

Core-level 4f_7/2 photoemission spectra have been measured from a single, bifacial W crystal, which has both a flat W(110) and a vicinal, stepped W(110) [W(320)] surface. This procedure reduces uncertainties in the quantitative description of peaks in the spectra from W(320). Various analyses, including nonlinear least-squares curve fitting, show that the average surface core-level shift (SCS) for W(320) is only ∼-140 meV, compared to -310 meV for W(110) and that, at a maximum, only two of five terrace rows are isoelectronic to W(110) surface atoms. The absence of a large SCS for the step-edge atoms contradicts earlier interpretations of W(320) core-level spectra and departs significantly from expectations based on atomic-coordination models or tight-binding calculations of a bulk truncated surface. We suggest that systematic errors are responsible for the differences in reported core-level shifts for W(320). Implications of possible step-edge-driven atomic rearrangements are discussed.

Comments

Published by American Physical Society in Physical Review B. Publisher PDF is available for download through link above.

Recommended Citation

"Surface Core-Level Shifts and Atomic Coordination at a Stepped W(110) Surface," D. M. Riffe, B. Kim, J. L. Erskine, and N. D. Shinn, Phys. Rev. B 50, 14481 (1994).