SPRING K

The parameter SPRING_K defines force constants [math]\displaystyle{ \kappa_{\mu} }[/math] for the harmonic bias of the following form: [math]\displaystyle{ \tilde{V}(\xi_1,\dots,\xi_{M_8}) = \sum_{\mu=1}^{M}\frac{1}{2}\kappa_{\mu} (\xi_{\mu}(q)-\xi_{0\mu})^2 \; }[/math] The