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arXiv · 1205.0122

First principles structures and circular dichroism spectra for the close-packed and the 7/2 motif of collagen

Karl J. Jalkanen·Kasper Olsen·Michaela Knapp-Mohammady·Jakob Bohr
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Abstract

The recently proposed close-packed motif for collagen is investigated using first principles semi-empirical wave function theory and Kohn-Sham density functional theory. Under these refinements the close-packed motif is shown to be stable. For the case of the 7/2 motif a similar stability exists. The electronic circular dichroism of the close-packed model has a significant negative bias and a large signal. An interesting feature of the close-packed structure is the existence of a central channel. Simulations show that, if hydrogen atoms are placed in the cavity, a chain of molecular hydrogens is formed suggesting a possible biological function for molecular hydrogen.

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Karl J. Jalkanen, Kasper Olsen, Michaela Knapp-Mohammady, Jakob Bohr. 2012-05-03. First principles structures and circular dichroism spectra for the close-packed and the 7/2 motif of collagen. https://doi.org/10.1209/0295-5075%2F100%2F28003

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