Any lattice vector r
in a real lattice can be written as:
 r = n_{1}a
+ n_{2}b + n_{3}c
where n_{i} are integers and a, b
and c are the unit vectors describing
the lattice.
These real space lattice vectors correspond to directions in the crystal. The lattice
vector can also be written as:
 r = ua + vb
+ wc
where u, v
and w are the components of the direction
index [uvw]. 


A reciprocal lattice vector can be defined in the same way:
 r* = m_{1}a*
+ m_{2}b* + m_{3}c*
where m_{i} are integers and a*, b*
and c* are the reciprocal unit
vectors.
This is more commonly written:
 g_{hkl} = ha*
+ kb* + lc*
where h, k,
l are
the Miller
indices of the plane (hkl).

Which
one of the statements about real and reciprocal lattice vectors below is true?