TY - JOUR
T1 - Structure of (FexCa1-xO)(y)(SiO2)(1-y) liquids and glasses from high-energy x-ray diffraction
T2 - Implications for the structure of natural basaltic magmas
AU - Drewitt, James W. E.
AU - Sanloup, Chrystele
AU - Bytchkov, Aleksei
AU - Brassamin, Severine
AU - Hennet, Louis
PY - 2013/6/3
Y1 - 2013/6/3
N2 - The atomistic structure of (FexCa1-xO)(y) (SiO2)(1-y) liquids, namely, fayalite (x = 1, y = 0.667), ferrosilite (x = 1, y = 0.5), and hedenbergite (x = 0.5, y = 0.5), was measured by using high-energy x-ray diffraction combined with laser-heated aerodynamic levitation. Measurements were also made for hedenbergite glass, formed via supercooling the liquid. The results unequivocally prove that Fe atoms are both four and sixfold coordinated by oxygen atoms in all compositions studied from the two distinct bond distances measured at r(FeO) = 1.93 and 2.20 angstrom, respectively. The results quantitatively reveal up to 40% and 55% FeO6 species residing in liquid fayalite and ferrosilite, respectively. From the real-space peak positions, the results also reveal the presence of both FeO4 and FeO6 species within a basaltic liquid and glass for which the geophysical consequences are briefly discussed.
AB - The atomistic structure of (FexCa1-xO)(y) (SiO2)(1-y) liquids, namely, fayalite (x = 1, y = 0.667), ferrosilite (x = 1, y = 0.5), and hedenbergite (x = 0.5, y = 0.5), was measured by using high-energy x-ray diffraction combined with laser-heated aerodynamic levitation. Measurements were also made for hedenbergite glass, formed via supercooling the liquid. The results unequivocally prove that Fe atoms are both four and sixfold coordinated by oxygen atoms in all compositions studied from the two distinct bond distances measured at r(FeO) = 1.93 and 2.20 angstrom, respectively. The results quantitatively reveal up to 40% and 55% FeO6 species residing in liquid fayalite and ferrosilite, respectively. From the real-space peak positions, the results also reveal the presence of both FeO4 and FeO6 species within a basaltic liquid and glass for which the geophysical consequences are briefly discussed.
KW - TEMPERATURE CRYSTAL-CHEMISTRY
KW - MOLTEN FEO-SIO2 SYSTEM
KW - HIGH-RESOLUTION XANES
KW - FE OXIDATION-STATE
KW - SILICATE-GLASSES
KW - FERROUS IRON
KW - MOLECULAR-DYNAMICS
KW - FE-57 MOSSBAUER
KW - AERODYNAMIC LEVITATION
KW - ALUMINOSILICATE GLASS
U2 - 10.1103/PhysRevB.87.224201
DO - 10.1103/PhysRevB.87.224201
M3 - Article (Academic Journal)
SN - 1098-0121
VL - 87
JO - Physical Review B: Condensed Matter and Materials Physics
JF - Physical Review B: Condensed Matter and Materials Physics
M1 - 224201
ER -