octahedron

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octahedron

oc·ta·he·dron

 (ŏk′tə-hē′drən)
n. pl. oc·ta·he·drons or oc·ta·he·dra (-drə)
A polyhedron with eight faces.

[Greek oktaedron, from neuter of oktaedros, having eight sides : okta-, octo- + -edros, sided; see -hedron.]

octahedron

or

octohedron

n, pl -drons or -dra (-drə)
(Mathematics) a solid figure having eight plane faces

oc•ta•he•dron

(ˌɒk təˈhi drən)

n., pl. -drons, -dra (-drə).
a solid figure having eight faces.
[1560–70; < Greek oktáedron eight-sided =okta- octa- + -edron -hedron]
oc`ta•he′dral, adj.

oc·ta·he·dron

(ŏk′tə-hē′drən)
A three-dimensional geometric figure with eight triangular faces.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.octahedron - any polyhedron having eight plane facesoctahedron - any polyhedron having eight plane faces
polyhedron - a solid figure bounded by plane polygons or faces
Translations
oktaedri
oktaéder
octaedro
oktaeder

octahedron

[ˈɒktəˈhiːdrən] N (octahedrons or octahedra (pl)) [ˈɒktəˈhiːdrə]octaedro m

octahedron

nOktaeder m, → Achtflächner m
References in periodicals archive ?
For the ZnO6 and WO6 octahedra, the symmetric and asymmetric deformation modes of the W-O and Zn-O bonds are observed at 560 and 432 [cm.sup.-1], respectively [3].
On the other hand, no tilting or rotation of the Ho[0.sub.6] and Nb[0.sub.6] octahedra is observed in the perfect cubic structure.
Clay minerals have a layered structure at the nanoscale, and each layer consists of some combinations of two layer types with silicon tetrahedra and aluminum octahedra as basic units [1, 2].
Recently, theoretical predictions and experimental results confirmed that the TaS2 built from the edge-sharing of Ta[S.sub.6] trigonal prisms exhibits superior catalytic performance in comparison with that of Ta[S.sub.6] octahedra [6, 7].
The investigation suggested that oxide ions move along the edges of columnar double octahedra in one direction, at one point passing through a bottleneck.It is just over one atom across but sufficient for oxygen to pass through, said Hester The researchers plan to investigate if oxide ion conductivity can be further improved by doping, a different degree of cation order/disorder and/or adopting larger cations.
This compound have three crystalline phases: rutile (tetragonal structure), anatase (octahedral structure), brookite (orthorhombic structure), which according to the requirement of the electrostatic valence rule, each oxygen atom is shared by three octahedra. For rutile each octahedron has two sides common with other octahedra; in brookite three and for anatase four sides shared by others octahedra.
Moreover, high frequency modes between 260 and 684 [cm.sup.-1] are attributed to Mn-O bending and stretching motion of the distorted octahedra and square pyramidal building block units.
As is shown in Fig 1a, MIL-53(Al) is consisted of infinite trans chains of AlO4(OH)2 octahedra interconnected by the 1,4-benzenedicarboxylate.
These forms have different crystal structures, being all of them distorted octahedra. The brookite polymorph crystallizes as an orthorhombic crystal system; rutile forms a distorted tetragonal system, and anatase a tetragonal crystal system [16-17].
Different values SA between VerB05 and Ver-SL05 were influenced by the nature of the cations in the interlayer and [Mg.sup.2+] in the octahedra, which were leached into the water.
Thenardite belongs to [F.sub.ddd] space group with octahedral structure of nearly regular S[O.sub.4] tetrahedra and distorted Na[O.sub.6] octahedra. The sodium atoms are each surrounded by 6 oxygen atoms each at 2.334 [Angstrom], 2.426 [Angstrom], and 2.534 [Angstrom] forming distorted Na[O.sub.6] octahedra with a two fold axis parallel to c-axis.