Lattice vector
= Lattice vector
{title2=$\mathbf R=\sum_i n_i\mathbf a_i,\quad n_i\in\mathbb Z$}
A direct lattice vector is an integer <linear combination> of primitive translation vectors $\mathbf a_i$ of a <Bravais lattice>. Translating by such a vector preserves the lattice. Its dot product with every <reciprocal lattice vector> is an integer multiple of $2\pi$ in the angular-wavevector convention.