Tt it stacking

Not only planar compounds but also nonplanar ones show tt-it stacking interaction. In the crystal structure of CuKLsslg 176), two... 

Relatively simple molecules with complementary functionalities may, under certain conditions, interact with one another to form significantly more complex supramolecular species, held together only by virtue of non-covalent interactions. Examples of such self-assembly processes are repeatedly found in nature. The DNA double-helix requires two complementary strands to become entwined via hydrogen bonds and tt-it stacking in a self-assembly process (see Chapter 1, Section 1.3). The strands recognise each other and join together to form the most thermodynamically stable assembly product. Protein folding and viral assembly operate in a broadly similar manner. 

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