Crystal and Electronic Structures and Linear Optics of Strontium Pyroborate

✍ Scribed by Q.-S. Lin; W.-D. Cheng; J.-T. Chen; J.-S. Huang

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 156 KB
• Volume: 144
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1998.8100

✦ Synopsis

The compound Sr 2 B 2 O 5 has been synthesized by high temperature solution reaction. It crystallizes in the monoclinic space group P2 1 /c with cell dimensions a‫,)4(917.7؍‬ b‫,)1(143.5؍‬ c‫)2(378.11؍‬A s , ‫,°°)2(17.29؍‬ V‫)3(9.884؍‬ A s 3 , and Z‫,4؍‬ D calc ‫؍‬ 3.76 g/cm 3 . The structure comprises SrO 7 and SrO 6 polyhedra and B 2 O 5 groups. The electronic structure has been calculated by the INDO/S method for this compound, and the dynamic refractive indices have been obtained in terms of INDO/SCI following combination with the sum-over-states method. The calculated energy gap is 4.26 eV between the upper valence band and lower conduction band, and the calculated average refractive index is 1.791 at a wavelength of 1.065 m. The charge transfers from O 2؊ anion orbitals to Sr 2؉ cation orbitals make the significant contributions to linear polarizability in terms of analyses of atomic state density contributing to the valence and conduction bands.