User talk:Logger9/Archives/2009/August

FCC solids

Could you please explain how and where File:Coll 3.jpg relates to "FCC crystal structure in a typical monatomic elastic solid" ? Thanks Materialscientist (talk) 03:35, 20 August 2009 (UTC)

The micrograph illustrates a detailed view of the typical crystal structure found in close-packed elemental solids. Furthermore, colloidal solids have been found to exhibit similar physical properties to classical elastic solids, with proper scaling considerations and adjustment for the lattice parameter. -- logger9 (talk) 18:36, 22 August 2009 (UTC)

I did understand your intention there, but please understand my deletion, which will continue until resolved: that picture has no crystalline order at all, as you can see by (a trained) naked eye, or if doubts, take a 2D Fourier transform, which is equivalent to measuring diffraction pattern, and observe absence of periodicity. Regards. Materialscientist (talk) 23:30, 22 August 2009 (UTC)

If you cannot see the long-range order in that micrograph, then your sense of order is clearly much different than that of a typical trained materials scientist. The fractured surface clearly illustrates a face centered cubic (FCC) packing structure with both (111) and (100) type planes visible, as confirmed by faculty members in Dept. of Materials Science & Engineering, UCLA School of Engineeering and Applied Science (1983).-- logger9 (talk) 05:38, 24 August 2009 (UTC)

With all do respect, I should not and do not rely on opinion of UCLA faculty members. No matter how (un)trained I am, I (or reader) should see long-range periodicity, which I do not. Ask anyone around if you don't believe. Could you show any extended atomic plane there ? Materialscientist (talk) 05:58, 24 August 2009 (UTC)

Easily. -- 23:00, 24 August 2009 (UTC)

So where :-) ? Materialscientist (talk) 23:30, 25 August 2009 (UTC)

The most continuous lines of symmetry are evidenced moving from the top right portion of the micrograph downwards. -- logger9 (talk) 00:06, 26 August 2009 (UTC)

Indeed, there a small crystalline island of uncertain crystalline symmetry near the top right corner. However, it extends to only a dozen of atoms and can not justify the whole picture being a crystal. I do understand what you wanted to say with this picture, but please understand my point that it just does not fit into its caption and purpose there. Figure 2 is much better. Materialscientist (talk) 01:12, 26 August 2009 (UTC)