67 k3_(k3), k2_(k2), k1_(k1), k0_(k0) {}
69 void setForceConstant(RealType k4, RealType k3, RealType k2, RealType k1,
78 void getForceConstant(RealType& k4, RealType& k3, RealType& k2,
79 RealType& k1, RealType& k0) {
87 virtual void calcForce(RealType cosPhi, RealType& V, RealType& dVdcosPhi) {
88 RealType cosPhi2 = cosPhi * cosPhi;
89 RealType cosPhi3 = cosPhi2 * cosPhi;
90 RealType cosPhi4 = cosPhi3 * cosPhi;
92 V = k0_ + k1_ * cosPhi + k2_ * cosPhi2 + k3_ * cosPhi3 + k4_ * cosPhi4;
94 k1_ + 2.0 * k2_ * cosPhi + 3.0 * k3_ * cosPhi2 + 4.0 * k4_ * cosPhi3;