/*
* The magnetic potential of an atom is always zero, because magnetic force does not do any work. But for a dipole
* moment, it is not zero.
*
* FIXME: I didn't find a closed-form solution for an electric dipole's magnetic potential.
*/
double getPotential(Particle p, float time) {
if (bounds != null && !bounds.contains(p.getRx(), p.getRy())) return 0;
double poten = 0.0;
if (p instanceof GayBerneParticle) {
GayBerneParticle gb = (GayBerneParticle) p;
if (Math.abs(gb.dipoleMoment) > 0) {
double temp = Math.sin(gb.theta) * gb.vx - Math.cos(gb.theta) * gb.vy;
if (o == OUTWARD) temp = -temp;
poten = gb.dipoleMoment * b * temp;
}
}
return poten;
}
void dyn(Particle p) {
if (bounds != null && !bounds.contains(p.getRx(), p.getRy())) return;
double temp = Math.abs(b) * p.charge * MDModel.GF_CONVERSION_CONSTANT / p.getMass();
if (o == OUTWARD) temp = -temp;
p.fx += temp * p.vy;
p.fy -= temp * p.vx;
if (p instanceof GayBerneParticle) {
GayBerneParticle gb = (GayBerneParticle) p;
if (Math.abs(gb.dipoleMoment) > 0) {
temp = Math.cos(gb.theta) * gb.vx + Math.sin(gb.theta) * gb.vy;
if (o == OUTWARD) temp = -temp;
gb.tau -= gb.dipoleMoment * temp * b / gb.inertia * MDModel.GF_CONVERSION_CONSTANT;
}
}
}