For the sixth series of The Hitchhiker's Guide to the Galaxy, see The Hitchhiker's Guide to the Galaxy Tertiary to Hexagonal Phases.
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Hexagonal phase" – news · newspapers · books · scholar · JSTOR(September 2014) (Learn how and when to remove this message)
Schematic of the molecular organisation in a type I hexagonal lyotropic liquid crystalline phase.
A hexagonal phase of lyotropic liquid crystal is formed by some amphiphilic molecules when they are mixed with water or another polar solvent. In this phase, the amphiphile molecules are aggregated into cylindrical structures of indefinite length and these cylindrical aggregates are disposed on a hexagonal lattice, giving the phase long-range orientational order.
In normal topology hexagonal phases, which are formed by type I amphiphiles, the hydrocarbon chains are contained within the cylindrical aggregates such that the polar-apolar interface has a positive mean curvature. Inverse topology hexagonal phases have water within the cylindrical aggregates and the hydrocarbon chains fill the voids between the hexagonally packed cylinders. Normal topology hexagonal phases are denoted by HI while inverse topology hexagonal phases are denoted by HII. When viewed by polarization microscopy, thin films of both normal and inverse topology hexagonal phases exhibit birefringence, giving rise to characteristic optical textures. Typically, these textures are smoke-like, fan-like or mosaic in appearance. The phases are highly viscous and small air bubbles trapped within the preparation have highly distorted shapes. Size and shapes of lamellar, micellar and hexagonal phases of lipid bilayer phase behavior and mixed lipid polymorphism in aqueous dispersions can be easily identified and characterized by negative staining transmission electron microscopy too.[1]
smokey optical texture of type I hexagonal phase
mosaic optical texture of type I hexagonal phase
mosaic/focal conic optical texture of type I hexagonal phase
^YashRoy R.C. (1990) Lamellar dispersion and phase separation of chloroplast membrane lipids by negative staining electron microscopy. Journal of Biosciences, vol.15(2), pp. 93-98. http://www.ias.ac.in/jarch/jbiosci/15/93-98.pdf
A hexagonalphase of lyotropic liquid crystal is formed by some amphiphilic molecules when they are mixed with water or another polar solvent. In this...
that is better for the body. The term "hexagonal water" refers to a cluster of water molecules forming a hexagonal shape that supposedly enhances nutrient...
Primary Phase of the groundbreaking radio series The Hitchhikers Guide to the Galaxy. Forty years later, he took the role of Marvin in the HexagonalPhase radio...
lamellar, hexagonal, and isotropic phases. Other techniques that are used and do offer definitive evidence of existence of lamellar and hexagonalphases include...
different phase dispersion structures, called lipid polymorphisms, for example, spherical micelles, lipid bilayer lamellae and hexagonalphase cylinders...
long-ranged hexagonal lattice. This lyotropic liquid crystalline phase is known as the 'hexagonalphase', or more specifically the 'normal topology' hexagonal phase...
with a surface structure reconstructed into a distorted hexagonalphase. This hexagonalphase is often referred to as a (28×5) structure, distorted and...
types: cubic MgCu2 (C15), hexagonal MgZn2 (C14), and hexagonal MgNi2 (C36). The latter two classes are unique forms of the hexagonal arrangement, but share...
hydrogen-bonded hexagonal rings are also the mechanism that causes liquid water to be densest at 4 °C. Close to 0 °C, tiny hexagonal ice Ih-like lattices...
30 nanometers. Two other phases, monoclinic and hexagonal, are known for this oxide. The formation of a certain Es2O3 phase depends on the preparation...
most stable crystalline form is the hexagonal one, also called h-BN, α-BN, g-BN, and graphitic boron nitride. Hexagonal boron nitride (point group = D3h;...
The Hitchhiker's Guide to the Galaxy Tertiary to Quintessential Phases and HexagonalPhase, as Wowbagger and Prostetnic Vogon Jeltz. He also appeared in...
galactolipids rather than phospholipids; also they predominantly consist of hexagonalphase II forming monogalacotosyl diglyceride lipid. Despite this unique composition...
two have hexagonal structure, similar to that of rhenium diboride. Osmium diboride was first also sought as hexagonal, but one of its phases was later...
Curie point. The compound metamorphosizes at 890 °C to the hexagonal close-packed Mn2N phase. Despite the name, Mn2N in fact exhibits substantial variation...
with two polymorphic phases can be called dimorphic, those with three polymorphic phases, trimorphic, etc. Phase transitions (phase changes) that help describe...