... constants¹

In other words, sum over $\vec{a}$ corresponds to some over all periodic images of atom at $\vec{R}_i$.

.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.

... found²

From private discussion with the main CONQUEST developer Dr. David Bowler.

.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.