SPRING K: Difference between revisions

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where the sum runs over all (<math>M_8</math>) coordinates  the potential acts upon (<math>\xi_{\mu}(q)</math>), which are defined in the {{FILE|ICONST}}-file by setting the <code>status</code> to 8.
where the sum runs over all (<math>M_8</math>) coordinates  the potential acts upon (<math>\xi_{\mu}(q)</math>), which are defined in the {{FILE|ICONST}}-file by setting the <code>status</code> to 8.
The units of <math>\kappa_{\mu} are <math>eV/uc</math> where <math>uc</math> units of coordinate the potential acts upon (e.g., <math>{\AA}</math> for coordinates with <code>flag</code> R, <math>rad.</math> for coordinates with <code>flag</code> A, dimensionless for coordinates with <code>flag</code> W, etc...)
The units of <math>\kappa_{\mu}</math> are <math>eV/uc</math> where <math>uc</math> units of coordinate the potential acts upon (e.g., <math>{\AA}</math> for coordinates with <code>flag</code> R, <math>rad.</math> for coordinates with <code>flag</code> A, dimensionless for coordinates with <code>flag</code> W, etc...)
The number of items defined via {{TAG|SPRING_K}} must be equal to <math>M_8</math>, otherwise the calculation terminates with an error message.
The number of items defined via {{TAG|SPRING_K}} must be equal to <math>M_8</math>, otherwise the calculation terminates with an error message.



Revision as of 08:21, 11 April 2023

SPRING_K = [real (array)] 

Description: 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] where the sum runs over all ([math]\displaystyle{ M_8 }[/math]) coordinates the potential acts upon ([math]\displaystyle{ \xi_{\mu}(q) }[/math]), which are defined in the ICONST-file by setting the status to 8. The units of [math]\displaystyle{ \kappa_{\mu} }[/math] are [math]\displaystyle{ eV/uc }[/math] where [math]\displaystyle{ uc }[/math] units of coordinate the potential acts upon (e.g., [math]\displaystyle{ {\AA} }[/math] for coordinates with flag R, [math]\displaystyle{ rad. }[/math] for coordinates with flag A, dimensionless for coordinates with flag W, etc...) The number of items defined via SPRING_K must be equal to [math]\displaystyle{ M_8 }[/math], otherwise the calculation terminates with an error message.


Related tags and articles

SPRING_R0 SPRING_V ICONST Biased molecular dynamics