SPRING_K

SPRING_K = [real (array)] 

Description: The parameter SPRING_K defines force constants ($\kappa _{\mu })$ for the harmonic bias of the following form:

${\tilde {V}}(\xi _{1},\dots ,\xi _{M_{8}})=\sum _{\mu =1}^{M}{\frac {1}{2}}\kappa _{\mu }(\xi _{\mu }(q)-\xi _{0\mu })^{2}\;$

where the sum runs over all ($M_{8}$) coordinates the potential acts upon ($\xi _{\mu }(q)$), which are defined in the ICONST-file by setting the status to 8. The units of $\kappa _{\mu }$ are $eV/uc$ where $uc$ units of coordinate the potential acts upon (e.g., ${\mathrm {\AA} }$ for coordinates with flag R, $rad.$ for coordinates with flag A, dimensionless for coordinates with flag W, etc...) The number of items defined via SPRING_K must be equal to $M_{8}$, otherwise the calculation terminates with an error message.

Related tags and articles

SPRING_R0 SPRING_V0 ICONST Biased molecular dynamics