Simple reason - It violates the cubic symmetry.
To see it from another perspective - Base centered cubic lattice is equivalent to a simple tetragonal lattice. Draw two unit cells adjacent to each other. Then connect the base center points to the corener points which are shared by these two unit cells. Then connect the two base centered point in each unit cell. Now you have a simple tetragonal lattice. Simple tetragonal lattice has one lattice point per unit cell compared to two lattice point per unit cell of base centered lattice. Always the lower lattice point lattice is considered for a given symmetry. Because of symmetry breaking, the symmetry of base centered cubic lattice is same as tetragonal lattice.
A metallic lattice consists of positive ions in a 'sea' of outershell negative electrons which are delocalised and mobile through the metal structure. The lattice is held together by strong forces of attraction between the mobile electrons and the positive ions.
In a face-centered cubic (fcc) lattice, each atom is in contact with 12 nearest neighbors. This means that the coordination number of a fcc lattice is 12.
The body-centered cubic system has a lattice point at each of the eight corner points of the unit cell plus one lattice point in the centre. Thus it has a net total of 2 lattice points per unit cell ( 1⁄8 × 8 + 1).The face-centered cubic system has lattice points on the faces of the cube, that each gives exactly one half contribution, in addition to the corner lattice points, giving a total of 4 lattice points per unit cell ( 1⁄8 × 8 from the corners plus  1⁄2 × 6 from the faces).
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.
When carbon is added to iron, the lattice structure transforms from pure iron's body-centered cubic to a face-centered cubic structure. This transformation results in the formation of steel, which has improved strength and hardness compared to pure iron.
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face centred cubic lattice is one in which there a atoms at the each edge and at the centre of each face
A metallic lattice consists of positive ions in a 'sea' of outershell negative electrons which are delocalised and mobile through the metal structure. The lattice is held together by strong forces of attraction between the mobile electrons and the positive ions.
What is a Hexagonal close packed lattice and what is sign it?"
It is a face-centered cubic lattice.
It is a face-centered cubic lattice.
Normally lead metal will have a cubic face centered lattice structure.
They are in a repeating, geometric pattern.A crystal's ions are arranged in an orderly, repeating, geometric pattern. Here's a link:http://www.scienceclarified.com/Co-Di/Crystal.htmlthey are happyin a orderly 3-D arrangement
Gold has a face centered cubic lattice.
Normally lead metal will have a cubic face centered lattice structure.
In a face-centered cubic (fcc) lattice, each atom is in contact with 12 nearest neighbors. This means that the coordination number of a fcc lattice is 12.
The crystalline structure of sodium chloride is face centered cubic.The crystalline structure of water is hexagonal.