eprintid: 1433814
rev_number: 27
eprint_status: archive
userid: 608
dir: disk0/01/43/38/14
datestamp: 2014-07-04 19:01:13
lastmod: 2021-10-04 01:37:38
status_changed: 2014-07-04 19:01:13
type: article
metadata_visibility: show
item_issues_count: 0
creators_name: Gao, DZ
creators_name: Grenz, J
creators_name: Watkins, MB
creators_name: Canova, FF
creators_name: Schwarz, A
creators_name: Wiesendanger, R
creators_name: Shluger, AL
title: Using Metallic Noncontact Atomic Force Microscope Tips for Imaging Insulators and Polar Molecules: Tip Characterization and Imaging Mechanisms
ispublished: pub
divisions: UCL
divisions: B04
divisions: C06
divisions: F60
keywords: NC-AFM, insulator, imaging mechanism, metallic tip, virtual AFM
note: © 2014 American Chemical Society. Terms of Use CC-BY. 

PubMed ID: 24787716
abstract: We demonstrate that using metallic tips for noncontact atomic force microscopy (NC-AFM) imaging at relatively large (>0.5 nm) tip–surface separations provides a reliable method for studying molecules on insulating surfaces with chemical resolution and greatly reduces the complexity of interpreting experimental data. The experimental NC-AFM imaging and theoretical simulations were carried out for the NiO(001) surface as well as adsorbed CO and Co-Salen molecules using Cr-coated Si tips. The experimental results and density functional theory calculations confirm that metallic tips possess a permanent electric dipole moment with its positive end oriented toward the sample. By analyzing the experimental data, we could directly determine the dipole moment of the Cr-coated tip. A model representing the metallic tip as a point dipole is described and shown to produce NC-AFM images of individual CO molecules adsorbed onto NiO(001) in good quantitative agreement with experimental results. Finally, we discuss methods for characterizing the structure of metal-coated tips and the application of these tips to imaging dipoles of large adsorbed molecules.
date: 2014-05
official_url: http://dx.doi.org/10.1021/nn501785q
oa_status: green
full_text_type: pub
primo: open
primo_central: open_green
verified: verified_manual
elements_source: WoS-Lite
elements_id: 960217
doi: 10.1021/nn501785q
lyricists_name: Shluger, Alexander
lyricists_name: Watkins, Matthew
lyricists_id: ASHLU39
lyricists_id: MWATK35
full_text_status: public
publication: ACS NANO
volume: 8
number: 5
pagerange: 5339 - 5351
issn: 1936-0851
citation:        Gao, DZ;    Grenz, J;    Watkins, MB;    Canova, FF;    Schwarz, A;    Wiesendanger, R;    Shluger, AL;      (2014)    Using Metallic Noncontact Atomic Force Microscope Tips for Imaging Insulators and Polar Molecules: Tip Characterization and Imaging Mechanisms.                   ACS NANO , 8  (5)   5339 - 5351.    10.1021/nn501785q <https://doi.org/10.1021/nn501785q>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/1433814/1/nn501785q.pdf