This is part of the multicolvar module

Add lower walls to a vector of quantities

Depracated action: use UPPER_WALLS

Quantity	Description
bias	the instantaneous value of the bias potential
force2	the instantaneous value of the squared force due to this bias potential

CATOMS	all the angles between the bonds that radiate out from these central atom are computed. For more information on how to specify lists of atoms see Groups and Virtual Atoms
GROUP	a list of angls between pairs of bonds connecting one of the atoms specified using the CATOM command and two of the atoms specified here are computed. For more information on how to specify lists of atoms see Groups and Virtual Atoms

DATA	the values you want to restrain
AT	the radius of the sphere
KAPPA	the force constant for the wall. The k_i in the expression for a wall.
OFFSET	( default=0.0 ) the offset for the start of the wall. The o_i in the expression for a wall.
EXP	( default=2.0 ) the powers for the walls. The e_i in the expression for a wall.
EPS	( default=1.0 ) the values for s_i in the expression for a wall
SWITCH	the switching function specifies that only those bonds that have a length that is less than a certain threshold are considered