RT Journal Article
T1 Crystallographic orientation inhomogeneity and crystal splitting in biogenic calcite
A1 Checa, Antonio G.
A1 Bonarski, Jan T.
A1 Willinger, Marc G.
A1 Faryna, Marek
A1 Berent, Katarzyna
A1 Kania, Bogusz
A1 González-Segura, Alicia
A1 Pina Martínez, Carlos Manuel
A1 Pospiech, Jan
A1 Morawiec, Adam
AB The calcitic prismatic units forming the outer shell of the bivalve Pinctada margaritifera have been analysed using scanning electron microscopy–electron back-scatter diffraction, transmission electron microscopy and atomic force microscopy. In the initial stages of growth, the individual prismatic unit sare single crystals. Their crystalline orientation is not consistent but rather changes gradually during growth. The gradients in crystallographic orientation occurmainly in a direction parallel to the long axis of the prism, i.e. perpendicular to the shell surface anddo not showpreferential tilting along anyof the calcite lattice axes. At a certain growth stage, gradients begin to spread and diverge, implying that the prismatic units split into several crystalline domains. In this way, a branched crystal, inwhich the ends of the branches are independent crystalline domains, is formed. At the nanometre scale, the material is composed of slightly misoriented domains, which are separated by planes approximately perpendicular to the c-axis. Orientational gradients and splitting processes are described in biocrystals for the first time and are undoubtedly related to the high content of intracrystalline organic molecules, although the way in which these act to induce the observed crystalline patterns is amatter of future research.
PB The Royal Society
SN ISSN: 1742-5689, ESSN: 1742-5662
YR 2013
FD 2013-09-06
LK https://hdl.handle.net/20.500.14352/34075
UL https://hdl.handle.net/20.500.14352/34075
LA eng
NO Ministerio de Ciencia e Innovación (MICINN)
NO Junta de Andalucía
DS Docta Complutense
RD 9 abr 2025