The CosineAngle interaction implements a potential that depends linearly on the cosine $\cos(\theta)$ of the bend angle. The energy is given by

$V(\theta) = \kappa [ 1 - \cos(\theta) ]$

Different values are defined for the parameters $\kappa$ and $\theta_{0}$ for each angle type.

The parameter file format is:

kappa Array<float>

The kappa array is entered in column form, with one entry per line, The angle interaction parameter block for a system with two angle types (nAngleType=2) might thus look like:

kappa 50.0

40.0