m) and NaCl is in the B2 structure (Pmm). The unit cell parameters of the (Mg0.25,Fe0.75)O-B1 and NaCl-B2 are 3.9112 (±0.0030) Å and 2.8034 (±0.0023) Å, respectively.Supporting information for Lin et al. (2003) Proc. Natl. Acad. Sci. USA, 10.1073/pnas.252782399.
Table 2. Observed and calculated x-ray diffraction peaks of (Mg0.25,Fe0.75)O and NaCl (thermal insulator) at approximately 79 GPa and 2270 (±150) K
h | k | l | d obs, Å | d calc, Å | d obs – dcalc, Å | Phase |
1 | 0 | 0 | 2.8038 | 2.8034 | 0.0004 | NaCl-B2 |
1 | 1 | 1 | 2.2594 | 2.2581 | 0.0012 | mw-B1 |
1 | 1 | 0 | 1.9813 | 1.9823 | –0.0010 | NaCl-B2 |
2 | 0 | 0 | 1.9537 | 1.9556 | –0.0019 | mw-B1 |
2 | 0 | 0 | 1.4032 | 1.4017 | 0.0015 | NaCl-B2 |
2 | 2 | 0 | 1.3825 | 1.3828 | –0.0003 | mw-B1 |
3 | 1 | 1 | 1.1789 | 1.1793 | –0.0004 | mw-B1 |
2 | 1 | 1 | 1.1437 | 1.1445 | –0.0008 | NaCl-B2 |
2 | 2 | 2 | 1.1302 | 1.1291 | –0.0011 | mw-B1 |
Le Bail and Rietveld refinements, performed with the GSAS program (1, 2), reveal that the sample is in the B1 structure (Fmm) and NaCl is in the B2 structure (Pmm). The unit cell parameters of the (Mg0.25,Fe0.75)O-B1 and NaCl-B2 are 3.9112 (±0.0030) Å and 2.8034 (±0.0023) Å, respectively.