eprintid: 1388053
rev_number: 33
eprint_status: archive
userid: 608
dir: disk0/01/38/80/53
datestamp: 2013-03-14 19:36:38
lastmod: 2021-09-17 22:29:10
status_changed: 2015-12-23 15:11:42
type: article
metadata_visibility: show
item_issues_count: 0
creators_name: Oganov, AR
creators_name: Hemley, RJ
creators_name: Hazen, RM
creators_name: Jones, AP
title: Structure, Bonding, and Mineralogy of Carbon at Extreme Conditions
ispublished: pub
divisions: UCL
divisions: B04
divisions: C06
divisions: F57
note: Copyright © Mineralogical Society of America 2013.
abstract: The nature and extent of Earth’s deep carbon cycle remains uncertain. This chapter considers high-pressure carbon-bearing minerals, including those of Earth’s mantle and core, as well as phases that might be found in the interiors of larger planets outside our solar system. These phases include both experimentally produced and theoretically predicted polymorphs of carbon dioxide, carbonates, carbides, silicate-carbonates, as well as very high-pressure phases of pure carbon. One theme in the search for possible high P-T, deep-Earth phases is the likely shift from sp2 bonding (trigonal coordination) to sp3 bonding (tetrahedral coordination) in carbon-bearing phases of the lower mantle and core, as exemplified by the graphite-to-diamond transition (Bundy et al. 1961; Davies 1984). A similar phenomenon has been documented in the preferred coordination spheres of many elements at high pressure. For example, silicon is ubiquitously found in tetrahedral coordination in crustal and upper mantle minerals, but adopts octahedral coordination in many high-pressure phases. Indeed, the boundary between Earth’s transition zone and lower mantle may be described as a crystal chemical shift from 4-coordinated to 6-coordinated silicon (Hazen and Finger 1978; Finger and Hazen 1991). Similarly, magnesium and calcium commonly occur in octahedral 6-coordination in minerals at ambient conditions, but transform to 8- or greater coordination in high-pressure phases, as exemplified by the calcite-to-aragonite transformation of CaCO3 and the pyroxene-to-perovskite and post-perovskite transformations of MgSiO3 (Murakami et al. 2004; Oganov and Ono 2004). Consequently, a principal focus in any consideration of deep-Earth carbon minerals must include carbon in higher coordination, and even more complex bonding at more extreme conditions that characterize the interiors of larger planets.
date: 2013-01
official_url: http://dx.doi.org/10.2138/rmg.2013.75.3
vfaculties: VMPS
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_source: Scopus
elements_id: 855557
doi: 10.2138/rmg.2013.75.3
lyricists_name: Jones, Adrian
lyricists_id: APJON49
full_text_status: public
publication: Reviews in Mineralogy and Geochemistry
volume: 75
number: 1
pagerange: 47 - 77
citation:        Oganov, AR;    Hemley, RJ;    Hazen, RM;    Jones, AP;      (2013)    Structure, Bonding, and Mineralogy of Carbon at Extreme Conditions.                   Reviews in Mineralogy and Geochemistry , 75  (1)   47 - 77.    10.2138/rmg.2013.75.3 <https://doi.org/10.2138/rmg.2013.75.3>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/1388053/1/Jones_Structure%2C%20Bonding%2C%20and%20Mineralogy%20of%20Carbon%20at%20Extreme%20Conditions_RIM075_C03.pdf