Splitting the 3[d.sup.3] electron energy level in the
octahedron can lead to an energy-level transition, which is directly associated with mineral colors [25].
One thing that really worked well with % my students was an
octahedron that I developed to be the format for them to investigate the Principles of Design.
Thus, the cube has 8 vertices, an
octahedron has 6, icosahedron has 12, a dodecahedron has 20, for a total of 46, which accounts for the first 92 elements or half of the Periodic Chart.
The paper gives a detailed analysis of several space-filling polyhedrons deployment, namely, cube deployment, hexagonal prism deployment, rhombic dodecahedron deployment, and truncated
octahedron deployment as shown in Figure 4.
Analogical geometrical relations can also be found creating a dynamic model of cubes and regular
octahedrons duality (Fig.
It was shown that a limited variation of
octahedrons or flat ellipsoids can provide optimized solutions, offering more realistic S/V-relationships as in the case of spheres, which is crucial for cement hydration (Bullard and Garboczi, 2006).
The very high prices which collectors have always been willing to pay for Alpine pink fluorite specimens have inspired unscrupulous sellers to glue fluorite crystals (or even cleavage
octahedrons) where they don't belong on matrix rock or on the faces of quartz crystals.
Joyce, "A 1.7-kilobase single-stranded DNA that folds into a nanoscale
octahedron" (2004) 427 Nature 618; Hao Yan et al., "DNA-templated self-assembly of protein arrays and highly conductive nanowires" Science 301 (26 September 2003) 1882.
In a feat of molecular engineering, scientists recently designed a strand of DNA that can spontaneously fold into an
octahedron.
As is well known, triclinic ZnMo[O.sub.4] is composed of a series of distorted Mo-O tetrahedrons, Zn-O pentahedrons, and ZnO
octahedrons. In a distorted Mo-O tetrahedron, the Mo atom is surrounded by four oxygen atoms.
The local coordination geometry of the two sodium centers[NaO6] could be best depicted as slightly distorted
octahedrons. The aromantic p-p stacking plays a considerable part in the constitution of 3D network.
Using the NMR and Mossbauer spectroscopy it was found that dissolution velocities of [Al.sup.3+] and [Fe.sup.3+] from
octahedrons and tetrahedrons of smectites are similar but with increasing replacement of Al for Mg and/or Fe the dissolution velocity from
octahedrons increases (Novak and Cicel, 1978).
