According to wikipedia, metallic cobalt occurs as hexagon close-packed and face-centred cubic.
Most metals and alloys crystallize in one of three very common structures: body-centered cubic (bcc), Li is an example of bcc , hexagonal close packed (hcp) Au is an example of hcp, or cubic close packed (ccp, also called face centered cubic, fcc) Ag is an example of fcg. The yield strength of a "perfect" single crystal of pure Al is ca. 10^6 psi.
In a cubic close-packed structure, each atom is in contact with 12 nearest neighbors. Each of these atoms has an octahedral void at its center. Therefore, the number of octahedral voids per atom in a cubic close-packed structure is 12.
a center faced cubic hexagonal closed pack structure focused in the minds eye is time travel or invention of the tartis.
Nickel is a metallic solid in the group of transition metals.
face centre cubic crystal has eight atoms in each corner and one atom in the centre of cubic unit cell.while hexagonal close packed structuree has only six atoms in corners but no in the centre of cubic cell
Magnesium has a hexagonal close-packed (hcp) crystalline structure. In this structure, the magnesium atoms are closely packed in layers, forming a hexagonal pattern. This arrangement gives magnesium its characteristic properties, such as high strength-to-weight ratio and good thermal conductivity.
Curium has a double hexagonal close packed crystalline structure.
as far as i know aluminum is a molecule not an atom. The aluminum atom has a valence of 3, what its chemical structure is depends on what it combines with.
It forms a face-centered cubic crystals. Under pressure these change to hexagonal close packed (hcp) crystals.
Closed packed derections.. are derections of the lines drawn through atoms such that no void space is in bitween.. Refer this, i also got the idea from here http://books.google.lk/books?id=wh4v6UWjYdIC&pg=PA5&dq=close%2Bpacked%2Bdirections&hl=en&ei=vo3WTKLbIYKYvAPp_ZXqCQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCYQ6AEwAA#v=onepage&q=close%2Bpacked%2Bdirections&f=false
Yes, zinc is a pure metal that adopts a hexagonal close-packed (HCP) crystal structure at room temperature. In its solid form, zinc atoms are arranged in a close-packed hexagonal lattice structure, making it an example of a pure metal with HCP arrangements.