- journal_title：American Mineralogist
- Contributor：Yue Meng ; Matthew Newville ; Steve Sutton ; John Rakovan ; Ho-Kwang Mao
- Publisher：Mineralogical Society of America
- Date：2003-
- Format：text/html
- Language：en
- journal_abbrev：American Mineralogist
- issn：0003-004X
- volume：88
- issue：10
- firstpage：1555
- section：Articles
Using synchrotron X-ray fluorescence (XRF) microanalysis, including XRF tomography, and X-ray absorption near-edge structure (XANES) analyses, the distribution, and nature of incorporation of Fe and Ni impurities in as-grown diamond crystals, synthesized under high-pressure and high-temperature (HPHT) conditions, have been characterized. We find significantly different behavior for Fe and Ni as impurities in diamond. Nickel is dispersed and sector-zoned, with concentrations in {111} growth sectors at least 3 times those in {100} sectors, whereas Fe exists in the form of micro-aggregates or clusters with no observable sector correlation. Fe K-edge XANES shows that Fe is oxidized in diamond and has a valence of 2+. Comparison of XANES spectra from numerous standard compounds indicates that Fe is very likely bonded with oxygen as FeO.