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Title: Step-doubling at Vicinal Ni(111) Surfaces Investigated with a Curved Crystal

Abstract

Here, vicinal surfaces may undergo structural transformations as a function of temperature or in the presence of adsorbates. Step-doubling, in which monatomic steps pair up forming double-atom high staircases, is the simplest example. Here we investigate the case of Ni(111) using a curved crystal surface, which allows us to explore the occurrence of step-doubling as a function of temperature and vicinal plane (miscut α and step type). We find a striking A-type ({100}-like microfacets) versus B-type ({111}-like) asymmetry towards step-doubling. The terrace-width distribution analysis performed from Scanning Tunneling Microscopy data points to elastic step interactions overcoming entropic effects at very small miscut α in A-type vicinals, as compared to B-type steps. For A-type vicinals, we elaborate the temperature/miscut phase diagram, on which we establish a critical miscut α c = 9.3° for step-doubling to take place.

Authors:
 [1];  [2];  [3];  [4];  [5]; ORCiD logo [6]; ORCiD logo [7]
  1. Centro de Fisica de Materiales CSIC/UPV-EHU-Materials Physics Center, San Sebastian (Spain); Donostia International Physics Centre, San Sebastian (Spain)
  2. Univ. del Pais Vasco, San Sebastian (Spain)
  3. Brookhaven National Lab. (BNL), Upton, NY (United States)
  4. CSIC-Univ. de Zaragoza, Zaragoza (Spain)
  5. Donostia International Physics Centre, San Sebastian (Spain); Basque Foundation for Science, Bilbao (Spain)
  6. Centro de Fisica de Materiales CSIC/UPV-EHU-Materials Physics Center, San Sebastian (Spain)
  7. Centro de Fisica de Materiales CSIC/UPV-EHU-Materials Physics Center, San Sebastian (Spain); Univ. del Pais, San Sebastian (Spain); Donostia International Physics Centre, San Sebastian (Spain)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1434767
Report Number(s):
BNL-203488-2018-JAAM
Journal ID: ISSN 1932-7447
Grant/Contract Number:
SC0012704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 121; Journal Issue: 7; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Ilyn, Max, Magana, Ana, Walter, Andrew Leigh, Lobo-Checa, Jorge, de Oteyza, Dimas G., Schiller, Frederik, and Ortega, J. Enrique. Step-doubling at Vicinal Ni(111) Surfaces Investigated with a Curved Crystal. United States: N. p., 2017. Web. doi:10.1021/acs.jpcc.6b11254.
Ilyn, Max, Magana, Ana, Walter, Andrew Leigh, Lobo-Checa, Jorge, de Oteyza, Dimas G., Schiller, Frederik, & Ortega, J. Enrique. Step-doubling at Vicinal Ni(111) Surfaces Investigated with a Curved Crystal. United States. doi:10.1021/acs.jpcc.6b11254.
Ilyn, Max, Magana, Ana, Walter, Andrew Leigh, Lobo-Checa, Jorge, de Oteyza, Dimas G., Schiller, Frederik, and Ortega, J. Enrique. Wed . "Step-doubling at Vicinal Ni(111) Surfaces Investigated with a Curved Crystal". United States. doi:10.1021/acs.jpcc.6b11254. https://www.osti.gov/servlets/purl/1434767.
@article{osti_1434767,
title = {Step-doubling at Vicinal Ni(111) Surfaces Investigated with a Curved Crystal},
author = {Ilyn, Max and Magana, Ana and Walter, Andrew Leigh and Lobo-Checa, Jorge and de Oteyza, Dimas G. and Schiller, Frederik and Ortega, J. Enrique},
abstractNote = {Here, vicinal surfaces may undergo structural transformations as a function of temperature or in the presence of adsorbates. Step-doubling, in which monatomic steps pair up forming double-atom high staircases, is the simplest example. Here we investigate the case of Ni(111) using a curved crystal surface, which allows us to explore the occurrence of step-doubling as a function of temperature and vicinal plane (miscut α and step type). We find a striking A-type ({100}-like microfacets) versus B-type ({111}-like) asymmetry towards step-doubling. The terrace-width distribution analysis performed from Scanning Tunneling Microscopy data points to elastic step interactions overcoming entropic effects at very small miscut α in A-type vicinals, as compared to B-type steps. For A-type vicinals, we elaborate the temperature/miscut phase diagram, on which we establish a critical miscut αc = 9.3° for step-doubling to take place.},
doi = {10.1021/acs.jpcc.6b11254},
journal = {Journal of Physical Chemistry. C},
number = 7,
volume = 121,
place = {United States},
year = {Wed Jan 25 00:00:00 EST 2017},
month = {Wed Jan 25 00:00:00 EST 2017}
}

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