<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>William A. Bassett</dc:contributor>
  <dc:contributor>Ho-kwang Mao</dc:contributor>
  <dc:contributor>I-Ming Chou</dc:contributor>
  <dc:contributor>Wendy Mao</dc:contributor>
  <dc:creator>Anat Shahar</dc:creator>
  <dc:date>2005</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;Raman analyses of single crystals of ikaite, CaCO&lt;/span&gt;&lt;sub&gt;3&lt;/sub&gt;&lt;span&gt;&amp;middot;6H&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;O, synthesized in a diamond-anvil cell at ambient temperature yield spectra from 0.14 to 4.08 GPa; the most intense peaks are at 228 and 1081 cm&lt;/span&gt;&lt;span&gt;&amp;minus;1&lt;/span&gt;&lt;span&gt;&amp;nbsp;corresponding to&amp;nbsp;&lt;/span&gt;&lt;i&gt;E&lt;/i&gt;&lt;sub&gt;&lt;i&gt;g&lt;/i&gt;&lt;/sub&gt;&lt;span&gt;(external) and&amp;nbsp;&lt;/span&gt;&lt;i&gt;A&lt;/i&gt;&lt;sub&gt;1&lt;i&gt;g&lt;/i&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;(internal) modes of vibrations in CO&lt;/span&gt;&lt;span&gt;2&amp;minus;&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;sub&gt;3&lt;/sub&gt;&lt;span&gt;&amp;nbsp;ions, respectively. These are in good agreement with Raman spectra previously published for ikaite in powder form at ambient temperature and pressure. Visual observations of a sample consisting initially of a mixture of calcite + water in a hydrothermal diamond-anvil cell yielded a&amp;nbsp;&lt;/span&gt;&lt;i&gt;P-T&lt;/i&gt;&lt;span&gt;&amp;nbsp;phase diagram up to 2 GPa and 120 &amp;deg;C; the boundary for the reaction ikaite &amp;harr; aragonite + water has a positive slope and is curved convexly toward the aragonite + water field similar to typical melt curves. This curvature can be explained in terms of the Clapeyron equation for a boundary between a solid phase and a more compressible liquid phase or largely liquid phase assemblage.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.2138/am.2005.1783</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Mineralogical Society of America</dc:publisher>
  <dc:title>The stability and Raman spectra of ikaite, CaCO&lt;sub&gt;3&lt;/sub&gt;·6H&lt;sub&gt;2&lt;/sub&gt;O, at high pressure and temperature</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>