a, b, c; or a_{i} 
Basis vectors of the direct lattice 
a, b, c 
Lengths of basis vectors, lengths of cell edges 
Lattice or cell parameters 
α, β, γ 
Interaxial (lattice) angles , , 
V 
Cell volume of the direct lattice 
G 
Matrix of the geometrical coefficients (metric tensor) of the direct lattice 

Element of metric matrix (tensor) G 
r; or x 
Position vector (of a point or an atom) 
r 
Length of the position vector r 
xa, yb, zc 
Components of the position vector r 
x, y, z; or 
Coordinates of a point (location of an atom) expressed in units of a, b, c; coordinates of end point of position vector r; coefficients of position vector r 

Column of point coordinates or vector coefficients 
t 
Translation vector 
t 
Length of the translation vector t 
; or 
Coefficients of translation vector t 

Column of coefficients of translation vector t 
u 
Vector with integral coefficients 
u, v, w; or 
Integers, coordinates of a (primitive) lattice point; coefficients of vector u 

Column of integral point coordinates or vector coefficients 
o 
Zero vector 
o 
Column of zero coefficients 
a′, b′, c′; or 
New basis vectors after a transformation of the coordinate system (basis transformation) 
r′; or x′; x′, y′, z′; or 
Position vector and point coordinates after a transformation of the coordinate system (basis transformation) 
; or ; , , ; or 
New position vector and point coordinates after a symmetry operation (motion) 