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

TL;DR

This study uses first principles calculations to analyze the stability and circular dichroism spectra of collagen motifs, revealing a stable close-packed structure with a potential biological function involving molecular hydrogen.

Contribution

It demonstrates the stability of the close-packed collagen motif and explores its electronic circular dichroism properties using advanced computational methods.

Findings

Close-packed motif is stable under refined calculations.

The motif exhibits significant negative bias in circular dichroism spectra.

A central channel in the structure may facilitate molecular hydrogen formation.

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.