Publication Date:
2004-07-17
Description:
We measured the spin state of iron in magnesium silicate perovskite (Mg(0.9),Fe(0.1))SiO(3) at high pressure and found two electronic transitions occurring at 70 gigapascals and at 120 gigapascals, corresponding to partial and full electron pairing in iron, respectively. The proportion of iron in the low spin state thus grows with depth, increasing the transparency of the mantle in the infrared region, with a maximum at pressures consistent with the D" layer above the core-mantle boundary. The resulting increase in radiative thermal conductivity suggests the existence of nonconvecting layers in the lowermost mantle.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Badro, James -- Rueff, Jean-Pascal -- Vanko, Gyorgy -- Monaco, Giulio -- Fiquet, Guillaume -- Guyot, Francois -- New York, N.Y. -- Science. 2004 Jul 16;305(5682):383-6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratoire de Mineralogie Cristallographie de Paris (UMR CNRS 7590), Institut de Physique du Globe de Paris, Universite Paris, 6 and 7, 4 Place Jussieu, 75252 Paris, France. james.badro@lmcp.jussieu.fr〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15256667" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
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Computer Science
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Medicine
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Natural Sciences in General
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Physics