TY - JOUR
T1 - What Lurks in the Martian Rocks and Soil? Investigations of Sulfates, Phosphates, and Perchlorates
T2 - Looking for jarosite on Mars: The low-temperature crystal structure of jarosite
AU - Mills, Stuart J.
AU - Nestola, Fabrizio
AU - Kahlenberg, Volker
AU - Christy, Andrew G.
AU - Hejny, Clivia
AU - Redhammer, Günther J.
PY - 2013/11/1
Y1 - 2013/11/1
N2 - Single-crystal diffraction of jarosite, KFe3 3+(SO4)2(OH)6, has been undertaken at low temperatures that proxy for martian surface conditions. Room-temperature data are consistent with literature data [a = 7.2913(5), c = 17.1744(17), and V = 790.72(11) in R3m], while the first low-temperature data for the mineral is presented (at 253, 213, 173, and 133 K). Data collections between 297 and 133 K show strongly anisotropic thermal expansion, with the c axis much more expandable than the a axis. Much of the anisotropy is due to strong distortion of the KO12 polyhedron, which increases by 8% between 297 and 133 K. The data sets can aid in the identification of jarosite by X-ray diffraction of martian soils using the Curiosity Rover's CheMin instrument.
AB - Single-crystal diffraction of jarosite, KFe3 3+(SO4)2(OH)6, has been undertaken at low temperatures that proxy for martian surface conditions. Room-temperature data are consistent with literature data [a = 7.2913(5), c = 17.1744(17), and V = 790.72(11) in R3m], while the first low-temperature data for the mineral is presented (at 253, 213, 173, and 133 K). Data collections between 297 and 133 K show strongly anisotropic thermal expansion, with the c axis much more expandable than the a axis. Much of the anisotropy is due to strong distortion of the KO12 polyhedron, which increases by 8% between 297 and 133 K. The data sets can aid in the identification of jarosite by X-ray diffraction of martian soils using the Curiosity Rover's CheMin instrument.
KW - Alunite supergroup
KW - Anisotropy
KW - Crystal structure
KW - Jarosite
KW - Low temperature
KW - Mars
UR - http://www.scopus.com/inward/record.url?scp=84888862800&partnerID=8YFLogxK
U2 - 10.2138/am.2013.4587
DO - 10.2138/am.2013.4587
M3 - Article
SN - 0003-004X
VL - 98
SP - 1966
EP - 1971
JO - American Mineralogist
JF - American Mineralogist
IS - 11-12
ER -