Reply to Comment on: “Properly interpreting scanning tunneling microscopy images: the Cu( [formula omitted])-c(2 × 2)N surface revisited”

• Published in: Surface science Vol. 539; no. 1; p. 186
• Main Authors: Wofford, T.E., York, S.M., Leibsle, F.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-08-2003
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/S0039-6028(03)00637-X

In reply to the preceding comment, first, let us state that we would hope that all interested parties would read all pertinent papers carefully before drawing their own conclusions. In particular, we wish to bring attention to recent results in which quenched molecular dynamic simulations suggest the lateral movement of Cu atoms within the Cu(100)-c(2 x 2)N structure. In our paper, we showed how STM tips with asymmetric apexes can distort the appearance and positions of features within unit cells and in some cases add additional features. In the instances in which we obtained STM images showing two protrusions imaged within a single c(2 x 2)N unit cell, we demonstrated that the second protrusion was due to a secondary protrusion on the tip located approximately 2.5 A from the main protrusion. We still believe this also explains the images of Driver and Woodruff. We do not agree that our images showed protrusions occurring over bridge sites. As to whether N atoms or Cu atoms should be imaged on Cu(100) surfaces, we note recent optimized density-functional calculations performed for the N/Cu(100) system indicate that indeed N atoms should be imaged over fourfold hollow sites.