Hello everyone,

I calculated the cohesive energy density of two atomic systems(Poly4-vinylpyridine(P4VP) and Poly2-vinylpyridine(P2VP)).

    Poly4-vinylpyridine(P4VP)                   Poly2-vinylpyridine(P2VP)

The two systems have one chain including twenty P4VP and P2VP monomers.

I found inter energy of the two systems are little different but total energy and intra energy of the two systems are quite different.

I would like to know what cause the difference of energy.

Best regards,

Martin