10.1021/jp503700g.s011
Ross T. DeVol
Ross T.
DeVol
Rebecca
A. Metzler
Rebecca
A.
Metzler
Lee Kabalah-Amitai
Lee
Kabalah-Amitai
Boaz Pokroy
Boaz
Pokroy
Yael Politi
Yael
Politi
Assaf Gal
Assaf
Gal
Lia Addadi
Lia
Addadi
Steve Weiner
Steve
Weiner
Alejandro Fernandez-Martinez
Alejandro
Fernandez-Martinez
Raffaella Demichelis
Raffaella
Demichelis
Julian D. Gale
Julian D.
Gale
Johannes Ihli
Johannes
Ihli
Fiona C. Meldrum
Fiona C.
Meldrum
Adam Z. Blonsky
Adam Z.
Blonsky
Christopher E. Killian
Christopher E.
Killian
C. B. Salling
C. B.
Salling
Anthony
T. Young
Anthony
T.
Young
Matthew A. Marcus
Matthew A.
Marcus
Andreas Scholl
Andreas
Scholl
Andrew Doran
Andrew
Doran
Catherine Jenkins
Catherine
Jenkins
Hans A. Bechtel
Hans A.
Bechtel
Pupa U. P. A. Gilbert
Pupa
U. P. A. Gilbert
Oxygen
Spectroscopy and Polarization-Dependent Imaging
Contrast (PIC)-Mapping of Calcium Carbonate Minerals and Biominerals
American Chemical Society
2014
PIC
calcium carbonate minerals
nacre
calcite
contrast
recording XANES spectra
Mytilus californianus shells
calcium carbonate
Calcium Carbonate Minerals
crystal
spectroscopy
spectromicroscopy
CaCO 3 biominerals
information
vaterite
aragonite
2014-07-17 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Oxygen_Spectroscopy_and_Polarization_Dependent_Imaging_Contrast_PIC_Mapping_of_Calcium_Carbonate_Minerals_and_Biominerals/2273632
X-ray
absorption near-edge structure (XANES) spectroscopy and spectromicroscopy
have been extensively used to characterize biominerals. Using either
Ca or C spectra, unique information has been obtained regarding amorphous
biominerals and nanocrystal orientations. Building on these results,
we demonstrate that recording XANES spectra of calcium carbonate at
the oxygen K-edge enables polarization-dependent imaging contrast
(PIC) mapping with unprecedented contrast, signal-to-noise ratio,
and magnification. O and Ca spectra are presented for six calcium
carbonate minerals: aragonite, calcite, vaterite, monohydrocalcite,
and both hydrated and anhydrous amorphous calcium carbonate. The crystalline
minerals reveal excellent agreement of the extent and direction of
polarization dependences in simulated and experimental XANES spectra due to X-ray linear dichroism. This effect is particularly strong
for aragonite, calcite, and vaterite. In natural biominerals, oxygen
PIC-mapping generated high-magnification maps of unprecedented clarity from nacre and prismatic
structures and their interface in Mytilus californianus shells. These maps revealed blocky aragonite
crystals at the nacre–prismatic boundary and the narrowest
calcite needle-prisms. In the tunic spicules of Herdmania
momus, O PIC-mapping revealed the size and arrangement
of some of the largest vaterite single crystals known. O spectroscopy
therefore enables the simultaneous measurement of chemical and orientational
information in CaCO<sub>3</sub> biominerals and is thus a powerful
means for analyzing these and other complex materials. As described
here, PIC-mapping and spectroscopy at the O K-edge are methods for
gathering valuable data that can be carried out using spectromicroscopy
beamlines at most synchrotrons without the expense of additional equipment.