---------------------------------
NOTES ON THE MODIFIED VERSION
---------------------------------

This version is built on the released 4.5.5 version and, with respect to
that one, this modification includes additional intramolecular potential 
terms coupling two internal coordinates. The new potentials are defined
in the topology files. The following ones are implemented (for the moment):

[ bo_di ] ; coupling between harmonic bond and flexible dihedral
; i1 i2        j1 j2 j3 j4   ft   r0   phi0   kij   nj  

[ an_di ] ; coupling between harmonic angle and flexible dihedral
; i1 i2 i3     j1 j2 j3 j4   ft   t0   phi0   kij   nj  

[ di_di ] ; coupling between flexible dihedral and flexible dihedral
; i1 i2 i3 i4  j1 j2 j3 j4   ft   phi_i   phi_j   kij   ni  nj  


Further details on the functional form of these couplings can be found at:
Cerezo, J.; Prampolini, G. & Cacelli, I. "Developing accurate intramolecular 
force fields for conjugated systems through explicit coupling terms"
Theor. Chem. Acc., 2018, 137, 80
URL: https://doi.org/10.1007/s00214-018-2254-8


---------------------------------
NOTES ON THE OFICIAL VERSION
---------------------------------


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