** Next:** 4.3 Indices of the set of
**Up:** 4. Crystallographic Calculations Using the Reciprocal
** Previous:** 4.1 Scalar product of direct and

Let us consider two direct lattice vectors:

Their vector product is equal to: Using the definition (2.1) of the basic reciprocal vectors, we may write:

(4.1) |

This shows that the vector product of two *direct* lattice vectors is
easily expressed in terms of the basic *reciprocal* vectors.

**Copyright © 1981, 1998 International Union of
Crystallography**