1. Tardigrade
  2. Question
  3. Chemistry
  4. Coordination numbers in a square close packed structure and hexagonal close packed structure respectively, are

Q. Coordination numbers in a square close packed structure and hexagonal close packed structure respectively, are

 1676  294 The Solid State Report Error

Solution:

Close packing in two-dimensions can be
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Type ______ type
The second row may be placed in contact with the first one such that the spheres of the second row are exactly above those of the first row. The spheres of the two rows are aligned horizontally as well as vertically. In this arrangement, each sphere is in contact with four of its neighbours.
Thus, its coordination number and is called square close packing in two-dimensions.
Atom is in contact with four others.
Type _______type
The second row may be placed above the first in a staggered manner such that its spheres fit in the depressions of the first row.
First row arrangement : type
Second row arrangement : type
Third row arrangement : type and so on
There is less free space and packing is more efficient than the square close packing. Each sphere is in contact with six of its neighbours and coordination number in two dimensions. It is called two-dimensional hexagonal close packing. Voids formed in this case are triangular in shape. If the apex of the triangles downward in the first row. It is upward in the second row.
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