Torsional potentials, Fourier component

Example This example of an HN-C(O) amide torsion uses the AMBER force field. The Fourier component with a periodicity of one (n = 1) also has a phase shift of 0 degrees. This component shows a maximum at a dihedral angle of 0 degrees and minima at both -180 and 180 degrees. The potential uses another Fourier component with a periodicity of two (n = 2). 

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