Electron Density Study of Garnets: Ca3(Cr, Al)2Si3O12

✍ Scribed by Haruo Sawada

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 223 KB
• Volume: 132
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1997.7460

✦ Synopsis

The electron density distribution in a natural garnet, uvarovite Ca 3 (Cr, Al) 2 Si 3 O 12 with 55% of the octahedral site occupied by Cr, has been studied with single-crystal X-ray diffraction methods through scattering factor refinement procedures. Electron density residuals up to 0.22 e/A s 3 in height indicating bonding electrons were detected between Si and oxygen. Characteristic aspherical electron density distribution around the (Cr, Al) site was also seen; six residuals, ؊0.27 e/A s 3 in height, are directed toward the coordinated oxygens, eight with 0.15 e/A s 3 height are directed away from the oxygens. [Cubic Ia3 d, a ‫؍‬ 11.956(1)A s ;