Vibrational and elastic properties of ferromagnesite across the electronic spin-pairing transition of iron
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Jung-Fu Lin
,
Jin Liu
Abstract
Ferromagnesite [(Mg,Fe)CO3] has been proposed as a candidate host mineral for carbon in the Earth’s mantle. Studying its physical and chemical properties at relevant pressures and temperatures helps our understanding of deep-carbon storage in the planet’s interior and on its surface. Here we have studied high-pressure vibrational and elastic properties of magnesian siderite [(Mg0.35Fe0.65)CO3] across the electronic spin transition by Raman and X-ray diffraction spectroscopies in a diamond-anvil cell. Our results show an increase in Raman shift of the observed lattice modes of magnesian siderite across the spin transition at 45 GPa as a result of an ∼8% unit-cell volume collapse and a 10% stiffer lattice (higher bulk modulus). C-O bond lengthening in the strong, rigid (CO3)2- unit across the spin transition contributes to a competitive decrease in Raman shift, most evident in the Raman shift decrease of the symmetric stretching mode. Combined vibrational and elastic results are used to derive the mode Grüneisen parameter of each mode, which drops significantly across the transition. These results suggest that the low-spin state has distinctive vibrational and elastic properties compared to the high-spin state. Analyses of all recent experimental results on the (Mg,Fe)CO3 system show no appreciable compositional effect on the transition pressure, indicating weak iron-iron exchange interactions. Our results provide new insight into understanding the effects of the spin transition on the vibrational, elastic, and thermodynamic properties of (Mg,Fe)CO3 as a candidate carbon-host in the deep mantle.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Veatchite: Structural relationships of the three polytypes
- Falsterite, Ca2MgMn2+2 (Fe2+0.5Fe3+0.5)4Zn4(PO4)8(OH)4(H2O)14, a new secondary phosphate mineral from the Palermo No. 1 pegmatite, North Groton, New Hampshire
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- Zaccagnaite-3R, a new Zn-Al hydrotalcite polytype from El Soplao cave (Cantabria, Spain)
- Incorporation of Si into TiO2 phases at high pressure
- TOF-SIMS and electron microprobe investigations of zoned magmatic orthopyroxenes: First results of trace and minor element analysis with implications for diffusion modeling
- Titanium in muscovite, biotite, and hornblende: Modeling, thermometry, and rutile activities of metapelites and amphibolites
- Polysaccharide-catalyzed nucleation and growth of disordered dolomite: A potential precursor of sedimentary dolomite
- High-pressure and high-temperature phase transitions in FeTiO3 and a new dense FeTi3O7 structure
- Compressibility and thermal expansion of hydrous ringwoodite with 2.5(3) wt% H2O
- Vibrational and elastic properties of ferromagnesite across the electronic spin-pairing transition of iron
- Electronic spin states of ferric and ferrous iron in the lower-mantle silicate perovskite
- Experimental VNIR reflectance spectroscopy of gypsum dehydration: Investigating the gypsum to bassanite transition
- Nature of rehydroxylation in dioctahedral 2:1 layer clay minerals
- Thermal behavior of afghanite, an ABABACAC member of the cancrinite group
- Experimental incorporation of Th into xenotime at middle to lower crustal P-T utilizing alkali-bearing fluids
- Sol-gel synthesis of nanocrystalline fayalite (Fe2SiO4)
- The heat capacity of fayalite at high temperatures
- Structural trends for celestite (SrSO4), anglesite (PbSO4), and barite (BaSO4): Confirmation of expected variations within the SO4 groups
- The dehydroxylation of serpentine group minerals
- Formation of nanoscale Th-coffinite
- Magnetic and low-temperature structural behavior of clinopyroxene-type FeGeO3: A neutron diffraction, magnetic susceptibility, and 57Fe Mössbauer study
- Crystal structure and thermal expansion of aragonite-group carbonates by single-crystal X-ray diffraction
- The lower-pressure stability of glaucophane in the presence of paragonite and quartz in the system Na2O-MgO-Al2O3-SiO2-H2O
- Coralloite, Mn2+Mn23+(AsO4)2(OH)2·4H2O, a new mixed valence Mn hydrate arsenate: Crystal structure and relationships with bermanite and whitmoreite mineral groups
- The crystal structure of metanatroautunite, Na[(UO2)(PO4)](H2O)3, from the Lake Boga Granite, Victoria, Australia
- Petedunnite (CaZnSi2O6): Stability and phase relations in the system CaO-ZnO-SiO2
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Articles in the same Issue
- Veatchite: Structural relationships of the three polytypes
- Falsterite, Ca2MgMn2+2 (Fe2+0.5Fe3+0.5)4Zn4(PO4)8(OH)4(H2O)14, a new secondary phosphate mineral from the Palermo No. 1 pegmatite, North Groton, New Hampshire
- Pavlovskyite Ca8(SiO4)2(Si3O10): A new mineral of altered silicate-carbonate xenoliths from the two Russian type localities, Birkhin massif, Baikal Lake area and Upper Chegem caldera, North Caucasus
- Zaccagnaite-3R, a new Zn-Al hydrotalcite polytype from El Soplao cave (Cantabria, Spain)
- Incorporation of Si into TiO2 phases at high pressure
- TOF-SIMS and electron microprobe investigations of zoned magmatic orthopyroxenes: First results of trace and minor element analysis with implications for diffusion modeling
- Titanium in muscovite, biotite, and hornblende: Modeling, thermometry, and rutile activities of metapelites and amphibolites
- Polysaccharide-catalyzed nucleation and growth of disordered dolomite: A potential precursor of sedimentary dolomite
- High-pressure and high-temperature phase transitions in FeTiO3 and a new dense FeTi3O7 structure
- Compressibility and thermal expansion of hydrous ringwoodite with 2.5(3) wt% H2O
- Vibrational and elastic properties of ferromagnesite across the electronic spin-pairing transition of iron
- Electronic spin states of ferric and ferrous iron in the lower-mantle silicate perovskite
- Experimental VNIR reflectance spectroscopy of gypsum dehydration: Investigating the gypsum to bassanite transition
- Nature of rehydroxylation in dioctahedral 2:1 layer clay minerals
- Thermal behavior of afghanite, an ABABACAC member of the cancrinite group
- Experimental incorporation of Th into xenotime at middle to lower crustal P-T utilizing alkali-bearing fluids
- Sol-gel synthesis of nanocrystalline fayalite (Fe2SiO4)
- The heat capacity of fayalite at high temperatures
- Structural trends for celestite (SrSO4), anglesite (PbSO4), and barite (BaSO4): Confirmation of expected variations within the SO4 groups
- The dehydroxylation of serpentine group minerals
- Formation of nanoscale Th-coffinite
- Magnetic and low-temperature structural behavior of clinopyroxene-type FeGeO3: A neutron diffraction, magnetic susceptibility, and 57Fe Mössbauer study
- Crystal structure and thermal expansion of aragonite-group carbonates by single-crystal X-ray diffraction
- The lower-pressure stability of glaucophane in the presence of paragonite and quartz in the system Na2O-MgO-Al2O3-SiO2-H2O
- Coralloite, Mn2+Mn23+(AsO4)2(OH)2·4H2O, a new mixed valence Mn hydrate arsenate: Crystal structure and relationships with bermanite and whitmoreite mineral groups
- The crystal structure of metanatroautunite, Na[(UO2)(PO4)](H2O)3, from the Lake Boga Granite, Victoria, Australia
- Petedunnite (CaZnSi2O6): Stability and phase relations in the system CaO-ZnO-SiO2
- Revision of the crystal structure and chemical formula of weeksite, K2(UO2)2(Si5O13)·4H2O
- Electron backscatter diffraction (EBSD) analyses of phyllosilicates in petrographic thin sections
