The second derivative of the pair energy, times the square of the
separation: r^2 d^2u/dr^2.
public abstract double uInt(double rC)
Integral of the potential, used to evaluate corrections for potential truncation.
Specifically, this is the integral from rC (the argument) to infinity of
u(r) A r^(D-1), where D is the spatial dimension, and A is the area of a unit
sphere in D dimensions. Normally, the long-range potential correction would be obtained
by multiplying this quantity by the pair density nPairs/V, where nPairs is the number of pairs of atoms
affected by this potential, and V is the volume they occupy.
Returns the same gradient as gradient(AtomSet) and also adds in the
contribution of the AtomSet to the pressureTensor. Their
contribution is added to the given Tensor. This combined method exists
for computational efficiency. Calculating the pressureTensor is
generally trivial once the gradient is known but often requires
Informs the potential of the box on which it acts. Typically this
requires at least that it update the nearestImageTransformer of its
coordinatePair (if it uses one), e.g.: