FBIAS_A = [real (array)]
Description: The flag FBIAS_A defines the size of step (
) for the Fermi-like step-shaped bias potential of the following form:
![{\displaystyle {\tilde {V}}(\xi _{1},\dots ,\xi _{M_{4}})=\sum _{\mu =1}^{M_{4}}{\frac {A_{\mu }}{1+{\text{exp}}\left[-D_{\mu }({\frac {\xi (q)}{\xi _{0\mu }}}-1)\right]}}\;}](https://www.vasp.at/wiki/restbase/vasp.at/v1/media/math/render/svg/c1b390dd7a8a941a831b4d11871d01f499f88380)
where the sum runs over all (
) coordinates the potential acts upon, which are defined in the ICONST-file by setting the status to 4.
The units of are 
.
The number of items defined via FBIAS_A must be equal to , otherwise the calculation terminates with an error message.
Related tags and articles
FBIAS_R0
FBIAS_D
ICONST
Biased molecular dynamics
