Towards Understanding the Atomistic Disorder of Synthetic Bone Mineral

Research Seminar abstract

Natural bone mineral most closely resembles the mineral calcium hydroxyapatite.  The compositional and structural disorder of the highly substitutable apatite has resulted in a poor atomistic understanding of the mineral phase of bone.  Although many studies using X-ray1 or neutron2,3 diffraction and computational1,4 experiments have attempted to understand the atomistic structure of synthetic and natural apatite samples, the question of the orientation of carbonate substitution into the lattice still remains ambiguous.  Through use of the atomic pair distribution function (PDF) analysis, a more detailed description of the local structure (r ≤10 Å) of the mineral can determined.  While the experimental PDF does not immediately show a preference for particular carbonate ion orientation, PDF is sensitive to the specific orientation of substitutions where X-ray diffraction is not.  Use of DFT-relaxed structures allows for the identification of the most energetically favorable substitution of carbonate into the mirror plane of the phosphate site which is most representative of the experimental PDF.  This analysis is a powerful tool which can aid the understanding of biomineralization processes and the role disorder can play.  Being able to predictably influence the crystallite morphology of synthetic materials will allow for the development of materials which more closely resemble their natural counterparts.

[1] Ivanova, Frank-Kamenetskaya, Kol’tsov, Ugolkov.  J. Solid State Chem. 2001, 160, 340-349.

[2] Leventouri, Chakoumakos, Papanearchou, Perdikatsis.  J. Mater. Res. 2001, 16, 2600-2606.

[3] Wilson, Elliot, Dowker, Smith.  Biomaterials. 2004, 25, 225-2213.

[4] Ulian, Valdrè, Corno, Ugliengo.  Am. Mineral. 2014, 99, 117-127.

Division(s): Physical

Speaker: Mary Marisa

Speaker Institution: Colorado State University

Event Date: 05-04-2017

Event Time: 4:00 PM

Event Location: Chemistry A101

Mixer Time: 3:45 PM

Mixer Location: Chemistry B101E

Host: J. Neilson