Observe the tilting of this silicon nano-sphere from it's four-fold symmetric <001> zone, first over a non-eucentric (e.g. tilt-stage) axis by 20 degrees, and then over an orthogonal eucentric (e.g. side-entry goniometer) axis by 29.6 degrees, so as to view fringes viewed down the <112> zone. The angle between starting and ending zones is a bit over 35 degrees. The set of tilts is important, however, because some high resolution microscopes can only tilt plus/minus ten degrees over one axis, and plus/minus 15 degrees over the other. It looks like the next generation of aberration-corrected high-resolution microscopes will offer a wider range of precise specimen orientations, thanks to longer working distances that the optics makes possible.
Hit reload to view the repeating two-tilt sequence again.
Here's the experiment Wentao did in conjunction with his Ph.D. thesis work using face-centered-cubic WC1-x.
How do the pattern of fringes before and after, expected from the diamond face-centered cubic crystal (model above), differ from the before and after pattern predicted (and verifed experimentally) for face-centered cubic crystals below?
