The last movie that I posted was of a columnar hexagonal phase. As I noted in that post, these phases are often not all that visually interesting, especially compared to nematic phases. This is partly due to symmetry and alignment effects; in a homeotropic orientation, the hexagonal phase is nonbirefringent. In contrast, columnar oblique phases are highly birefringent. The following movie shows an oblique phase growing in from the higher temperature nematic phase. This transition has been featured in earlier photos on this blog, but the movie tells a more dramatic picture:
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Vance Williams
is a Professor of Chemistry at Simon Fraser University. Archives
October 2015
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